It depends on what you have. If you have a PS3 or Xbox 360 or something, and you don't have a really good computer, I'd save up for a nice, new, good computer.
If you don't have PS3/Xbox then get one, of course, if you're not a "hardcore" PC gamer...
Nevertheless, something always nice to invest in is a cell phone, or if you're looking into something a little less pricey, considering you have to always pay something every month, get an iPod touch or something. The new ones. I have one and it's nice.
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stuff. A poll? Whatever, just take into consideration what I have too.