Here is my 1988 Cannondale with original Shimano 105 components and Bio-pace chainring. I have ridden it in Triathlons and Duathlons for about 5 seasons now and have made the following upgrades during that time:
2006 - bone stock (except for clipless pedals)
2007 - Profile airstryke aerobars w/ swift shift mount and Nitto forward seat post
2008 - Profile aerodrink bottle
2009 - Lazer Chrono aero helmet
2011 - Zipp 404's, 9-speed 11-23 cassette, carbon fork, Adamo saddle and aqua rack (rear bottle mount)