If I only had the $$ for new cards.
At least I can play

Yeah this is what I normally do when a good card comes out like 2-3 weeks before release or duing release I sell my old cards at 50-75% of what the retail price is. If its a generation below the ones out currently but the same chip like a 280 and the one out is a 285 I drop my price by about 40-65% of the retail price. sold my 280 GTX FTW's at around 200 or so dollars right when the GTX 480 came out. There are guys now selling their GTX 480's for 370-390 dollars shipped on the evga forums because of the new 580's coming out soon 15-20% faster in games than the GTX 480 and 30% faster in vantage than the 480. Me I buy the first gen so I get the full or almost full 2-3 years out of my card and still can get at least or close to the 40-65% of what I paid for them. I will be skipping the GTX 580 its a revised fermi chip should had been called the GTX 485 but whatever nvidia does what they want and always names things strange... Ill wait until 2012-2013 to upgrade to the latest and greatest and will still be able to get 170-200 dollars for the cards I paid 500 for one at pre order launch was one of the firest 20 people in the united states consumer wise to have one, the second I paid 380 dollars for using a mail in rebate and my EVGA bucks. But that is the best way to upgrade. I also keep old video cards I liked that did me right aka favorites, I always keep one so if I sell before the latest card is that comes out I have a gpu to fall back on to tide me over until I have a new gpu in my hands. I never buy revision gpus you only get about 1-1.5 years out of them sometimes less than that. I pretty much avoided the 9 series like the plague. Since my 8800 Ultra could still wamp a 9800GX2 in higher resolution eye candy cranked up games.
That is prob the best way to upgrade gpus at least, as for extreme cpus i wait to get them for 200-600 dollars cheaper than what they are new, with a soon release or rumored release of the latest and greatest cpu. like the 990x was supposed to be out in sept so guys started selling their 980x's at 200-400 cheaper than retail and of course I jumped on mine=)