I can only speak about parts I used, so here's my list:
Marzocchi Z1/Z2 - I have at least 4 of these and they are still running smooth as butter, as they should. Met Bryson Martin this summer at the Worlds, said thanks for the great product, became friends. What a great guy!
Chris King headset - Mine is a 1996. Need I say more?
Azonic Shorty / Kore B-52 / AC DH/ Syncros Cattlehead hinged stems - When there was an array of stems with personality out there, I lusted after these. Now I have them and they are pieces of art.
Answer Pro Taper / Race Face Air Alloy Riser bars - The Pro Taper is in a class of its own, but the Air Alloy Riser is overlooked and almost as good.
Any lock-on grips, really.
Flite - No need for argumentation, I hope. I have five of them.
Hope / Salsa / Mavic / Kore / Shimano alloy QRs - I broke a few Salsas and repaired them, but as a functional item that is able to be aesthetic, the Shimanos are hard to beat. Can't use them as tire levers, though.
Shimano XTR M900 cranks - I have quite a few cranks, but these are amazing. Also a honorable mention for my classy Profile tubulars!
Shimano XTR M900 / Deore XT M737 rear derailleurs - Still going and I cand hardly believe it.
Top shelf GripShift - Didn't have any choice and they proved to be killer. I also learned how to deal with my own silly prejudice.
Shimano Deore 2-way release STI levers - They are newschool, ugly and cheap, but they are ergonomic and do their job. Somehow I have 3 pairs of these. I love the idea of an underrated product that works a good as the more expensive one. I always had the feeling that STX-RC and Deore had stiffer springs in their levers than the soft Deore LX.
Shimano BR-M600 brakes - They brought power to the brake market and truly democratized this realm. The most copied brake ever and it can be set up with an allen key and a hand. Who needs a screwdriver to tension springs?
Hayes MX-2/MX-4 brakes - Not oldschool, but a classic because they are cheap and work well. BB7 is better, but also more expensive. Democracy to the brake market, part two! Pair them with cheap Avid FR5 levers and there you go. Honestly, nobody needs more brake lever than this.
Sapim spokes - Kick the Swiss in the nads. Polyax nipples a long time before there was Pro Lock on DTs and a slightly better quality at the same price. Nipples don't get twisted as easily as newer DTs. "They don't make 'em like they used to" is a quote to remember for the Swiss.
Michelin rubber - Maxxis only copied from here and then became big. I keep my Transalps with pride, because I know what they are and what they do.
And finally...
Mavic D521/EX721 rims - Still World Cup standard, still to be found on many new bikes, still a riders' choice. Back in the day, the Global team used to stack them painted yellow to replace the standard DeeMax rims (D321) that they had. Peat, Vouilloz, Minnaar and a lot of others rode them and swore by them. I honestly can't recall how many I have, but they are everywhere: on my newschool DH bike, on my dirtjumping hardtail, on an XC bike and who knows where else. Last week I rode my 2002 Jekyll two times on the edge and had to ride some kilometers on a rear flat. Do you think the rims were impressed? Hardly! I weigh 95+ kg and they still stood true, no problem. Amazing! The best rim in the world, period! It's no wonder Mavic kept it that way since 1998.
That's it from me.
Cheers guys!
Mx