Too poor or uninterested to go out and buy a HD TV for your gaming needs? Personally, I don't watch TV. So the only thing I would use a television set for is video games ..and maybe some DVDs every now and then. That's not worth a few hundred or thousands of my earnings just so I can read the text messages in GTA... (Trust me, those are impossible to read on my previously-used 32" tube SDTV)
You gotta computer? Most modern-day personal computer monitors are in HD and have an HDMI input. Plug it in. ...and you don't have to unplug the cable to get back to your Facebook page... there should be a source selection button to toggle between inputs.
Yours doesn't have an HDMI input? No problem. Go online and order an HDMI to DVI cable (got mine on eBay for $8. Don't go to a store 'cause most stores don't carry it and those that do charge $50+)... plug it from your PS3/xBox to your computer monitor... there you go, HD gaming!!!
Most computer monitors have two to three inputs; one digital and one analog and maybe an HDMI ...and you can switch back and forth without unplugging the cables..I use the Digital for my PS3 and the analog for the computer. (Mine's a couple years old so it doesn't have an HDMI input... but it does have 1440 x 900 pixels of HD gaming capacity; more than many of my friends who play on a big screen 720!!)