Please only provide definitive approximate numbers from knwowledge/first hand experience, so people can get a feel of whats possible still.
Do you drive down the road looking only in your rear-view mirror?
If not, then you don't want to know how much people have been making with their mining rigs recently and in the past, but instead you want to look at where mining is headed.
ASICMINER and Avalon ASIC are absolutely blasting difficulty up. If it weren't for the corresponding rise in the exchange rate, you would get hundreds of PMs from people offering to dump their old ATI Radeons on you. Give it a couple weeks, that's coming. And that is even before BFL has shipped.
So, ...
Either look at Litecoin for GPU mining, which is currently roughly approximate to being as profitable as Bitcoin mining, or find a new fun game to play on that GPU.