Alchemists
I think that Alchemists see a lot less business than they might simply because many players do not understand the kinds of services they are able to provide or the value of those services. People might have some idea that they provide certain potions to high level eq parties and players attempting to solo quests, but don't generally give them much thought aside from that. It's true that Alchemists will probably never have a direct impact on the daily routines of normal players, but there are a fair number more situations where their abilities can be an asset than most people assume. Some of the specific situations where an alchemist is your first best hope of success:
Potions and their uses:
1. No-magic quests. Some quests and areas have restrictions on them that make it difficult for one to take advantage of magical assistance. However, since alchemist potions produce effects without spellcasting, they can provide a significant edge to a tank without backrow assistance. Perhaps the most famous example of this is Ackbar's Warrior Shrine, however Victi Vicimus and Way of the Warrior also fall into the category.
2. No-highbie quests. Level restricted quest areas are perhaps the most hated in the game. The adage "You are who you know." is very applicable to Batmud, and being unable to call upon the aid of your friends during a quest is a frustrating experience indeed. All too often the true newbies you might ask for help are lacking even the most basic equipment. Worse, they are equally often incompetent, inattentive, and petulant nitwits. An assortment of offensive and defensive alchemist potions might sound pricey, but starts to look a whole lot more attractive after your new level 30 ranger friend goes idle during combat for the tenth time and quits when he gets himself killed. Even when you manage to find a jewel as bright as a newbie who listens to you, giving him the ability to toss blasts at the physress boss monster makes a wonderful thing all the better! The elemental towers are perhaps the best example of an obnoxious quest that can be made more bearable with blasting newbies (Yes, I know that it is "possible" to get high level help with that one), but one shouldn't have much difficulty thinking of other places where those 'crappy overpriced blast potions' start looking like diamonds.
3. Specialist spells and skills. Some eq parties are made or broken on a few tricks and abilities. The opportunities created when someone gets access to the exclusive class skills of entirely different backgrounds should be evident to anyone with some imagination.
4. Critical to succeed. Potions succeed pretty reliably. They can fumble, but the effects are often random oddities rather than a standard fumble effect.
5. Ungettable skills. Alchemists can grant some of the harder to get abilities. These include potions of: possessions, inform, indoors disguise, outdoors disguise, slip, and glance. Sometimes useless, but use a little creativity and you can do some fun things.
Other Alchemist Services:
1. Patch item. Using dragonscale to repair equipment is rather expensive, but it can pale beside the cost of some of the ultrarare or nigh ungettable materials.
2. Salves. These have never really taken off in popularity, by which I mean they just aren't ever used. I figure it's kind of a shame, given some can give a decent enough boost to resistances.
3. Drugs. I've never entirely figured out why people suck down thrikhren's ubernasty racial penalties when they could just partake of some brainstormer from time to time and play a race that doesn't require multiple meg reinc fees every month.
4. Rings. Alch rings are dead, long live eckmas. Seriously though, alch rings are by no means terrible, but these days you have precious little chance of finding one with good stats that are also stats you need.
5. Booze. Well, it's not like the mixmasters are limited to just stodgy old glowing flasks full of spells. Alchemists have a few interesting abilities that relate purely to alcohol.
6. Elixirs. I've never used one, but these special concoctions are supoosed to give utterly massive attribute bonuses to those who can afford them.
Drawbacks when utilizing alchemists:
Potions are sold at ripoff prices unless you buy in bulk or have an alch friend who owes you a save or two, in which case they are merely overpriced. On the plus side, keep in mind that all potions can generally be used two or three times. Also, since cash is useless these days, you can feel free to go hog wild unless you reinc too much!
A second problem is that the potion exchange is not very good, though it isn't as insultingly useless as it was in the past.
Potion list:
acid arrow acid rain acid wind all-seeing eye anti magic field appraise aura detection aura of hate banish baptize battlecry blacksmithing blast lightning bless bless armament blessing of tarmalen blurred image burial ceremony call pigeon camouflage camping cardiac stimulation cash flow ceremony chain lightning chaos bolt chill touch clairvoyance cold tolerance compare cone of cold consider corrosion shield create air armour create food credit check cure critical wounds cure player curse of tarmalen damn armament dark baptism dark meditation darkfire darkness deaths door desecrate ground destructive rage detect alignment detect poison dimension door dispel magical protection displacement disruption drying wind earth skin energy channelling ether boundary evil intent feather weight field of fear field of light fire blast fire building fire walking firebolt first aid flame arrow flaming ice flex shield flip floating floating disc floating letters force absorption force dome force shield forest location fresh pants frost insulation glance go good berry guardian angel haste heal self hear noises heat reduction heavy weight hiding holy way identify indoors disguise inform infravision invisibility iron will leather craft lessen poison levin bolt life link light lightning bolt locate water location memory lumberjacking magic dispersion magic missile magic wave mana shield meditation mental glance mental watch meteor swarm mind blast mind store mirror image mobile cannon money over matter? moon sense natural renewal neutrilize field outdoors disguise pain threshold phaze shift plastic surgery poison blast poison spray possessions preserve corpse protect armour protect item protect weapon protection from evil protection from good psi blast psibolt psionic shield psychic sanctuary psychich shout quicksilver rain regeneration remote banking remove scar repair item replenish energy resist disintegrate resist dispel resist entropy resist gasous form restore satiate person scouting sculpture see invisible see magic see the light sewing sex change shapechange shelter shield of faith shocking grasp skinning slip sneak soul hold soul shield stargazing suffocation summon lesser spores teleport with error teleport without error tempt terror there not there thorn spray torch creation toxic dilution toxic immunity track transmute self travel uncontrollable hideous laughter unpain unstable mutation unstun vacuum ball vacuumbolt venom strike ventriloquism vine mantle water walking wilderness location wipe tracks wizard eye woodland stealth