Just purchased my 1993 Volvo 850GLT a few weeks ago. Not much done to it now since I just got it but I've put 20% smoke tint on it and installed part of my system:
Alpine CD player
2 JL Audio 12w3 subs
Power Acoustik OV2-1200 (1200watt amp)

Future plans are to have all JL Audio speakers and to have a center channel for compete sound imagery. I also plan to turbo it with very minor internal motor work to add to the engine life span. 17 inch wheels are on the way but I dont want to lower it for ride quality purposes. Page and car are under construction, more added later!!!