I have no medications or health problems, big strong guy, but help keep it that way with 23 pills in the middle of breakfast each day. Gak! Plus some related things. Lots of info here, in order of priority:

1) FOR DAILY FUNCTIONING
Water -- Drinks lots of water constantly! Most headaches, or poor muscle and joint function are due to insufficient water. It lubricates, flushes, keeps everything working. I try to drink a 12oz glass every couple hours, but it varies a lot.
Humidifier -- Living at 6200 feet altitude, the air is drier than any desert. Folks here are always dealing with chapped skin and a constant cough and nasal drip from throat irritation. Humidifiers are mandatory, to raise the humidity from 18% to 46%. AAaaahhhh....
Sunblock -- Anytime I'm out more than an hour. Some after-bath lotions are now SPF-45, to moisterize AND prepare for the day.

2) FOR OVERALL HEALTH
Three different multivitamins:
1 Rite-Aid Central-Vite
1 Whole Source
1 Trader Joe's -- sustained release
I take half dosage of three different kinds because I'm tired of reading how one manufacturer or another has better quality, easier to digest, more usable, etc, etc. Here, if one brand sucks maybe the other will get it right.
1 glass of wine or a beer each day
Studies have shown blah, blah, heart risk, blah, blah, tension, blah, blah, adds years. Red wine is supposed to be the best (sulfates? dunno)
Good Spirit -- It's not so much what you eat, but the spirit of HOW you eat it. If I smile each day, eat slowly enough to really enjoy every bite, laugh often and have a spring in my step, I can burn major calories just by walking across the room. Since I can turn my metabolism up or down to keep myself warm or cool, why not choose HOW to be throughout the day?
The important thing is to Enjoy !

3) FOR IMMUNITY AND LONGEVITY
3000 mg Vitamin C -- That's the maximum your body can absorb in 24 hours, so I take the time-release variety. For people who "megadose", only an I.V. drip can provide you more.
325 mg Buffered Aspirin -- thins blood, reduces arterial buildup and risk of heart attack. Yeah, I know Bayer did the study but who cares, sounds good.
Multi Anti-Oxidant -- I've read too many articles about destructive free radicals. Our society has so many new harsh chemicals oxidizing and breaking down our biochemisty! Anti-oxidants probably don't hurt, but have the potential to help treMENDously. It's mostly redundant with Vitamin A, C, E, but has a few other things too.
Odorless Garlic -- Also more likely to help than hurt. Cheap too.
200 mcg Chromium Picolinate -- somebody recommended it, dunno why.

4) FOR DAILY STRENGTH AND ENDURANCE
Webber, Joint Support (300 mg MSM, 200 MG Glucosamine, 240 mg Chondroitin)
Nature Made, Triple Flex (375 mg MSM, 1500 mg Glucosamine, 1200 mg Chondroitin)
Also, 500 mg L-Lysine
With heavy exercise, tweaked joints recover much quicker and last longer. Also, a friend has arthritis and these make her continuous pain go completely away. I'd just like to keep my joints healthy.
1000 mg Siberian Ginseng -- gives me more energy to last all day.
1000 mg Three Ginsengs -- because each type has its own limitations.
100 mg Vitamin B -- Doctor recommended 800 mg/day megadose to help a sprained back recover. Since then I just keep up.
400 I.U. Vitamin E -- My skin gets thrashed by weather. Helps recovery.
25,000 I.U. Beta Carotene (Pro-Vitamin A) -- A friend recommended, dunno why.
50 mg CoEnzyme Q10 (Ubiquinone) -- Digestion changes in older people (at about 35). Maybe this'll help get all the natural wholesome goodness from the manufactured foods I eat.

MODIFICATION DURING COLDS
Yin Chow -- a chinese herbal remedy kicks most colds hard, if you take it right at the start.
Echinacea -- boosts immunity, esp. to viruses.
GoldenSeal -- great for bacterial infections. Because it's over-harvested, I avoid taking unless needed.
Like antibiotics or steroids, taking these continuously makes them ineffective. Save them for when you really need 'em.

MODIFICATION FOR HEAVY EXERCISE
Bicycling 180 miles I may lose as much as 20 pounds in 12 hours.
That's about 2.5 gallons of water lost, even after drinking 2 gallons.
I'm no expert and half of what I believe is crap. But I have physically noticed:
Carbo drinks help keep the energy up during exercise.
A big dose of protein (50-70g shake) immediately afterwards helps stretched and torn muscles heal about twice as fast, then I'm ready to go again with one day rest instead of two. A lot less stiffness and pain too.

OBSESSIVE AND UNNECESSARY?
Probably. But I pack my own small zip-lock bags once a month, and don't even think about it except 30 seconds each day.
The $600/year is pretty cheap if it buys me one more year of longevity,
not to mention running around with just a tad more energy.
I'd pop for that!