If you enter your Steam ID on http://www.mysteamgauge.com/ you will get some interesting stats like this: Over the last 9 years, you've spent 95.4 hours playing this selection, which includes 214 items, is valued at $2478.04, and requires 620.2 GB I used to game a lot more before Steam started tracking play time... honest!
Over the last 3 years, you've spent 867.3 hours playing this selection, which includes 177 items, is valued at $2524.41, and requires 800.8 GB Erm... Yeh...
Over the last 3 years, you've spent 13.1 hours playing this selection, which includes 39 items, is valued at $372.68, and requires 83.6 GB Just recently been adding to my collection since I bought a new computer a few months ago.
Over the last 6 years, you've spent 1323.6 hours playing this selection, which includes 38 items, is valued at $381.73, and requires 148 GB
Over the last 10 years, you've spent 597.2 hours playing this selection, which includes 226 items, is valued at $2725.98, and requires 683.3 GB
Over the last 4 years, you've spent 228.8 hours playing this selection, which includes 215 items, is valued at $2273.2, and requires 633.3 GB And I haven't spent a euro...