Help forums. If you can get one of these things active you can actually make some dough off of it.
I say help forums for one reason only: Other people will voluntarily give you actively updated content, while you can sit back and concentrate on making the design/function better or, if you're like me, how to make some cash off of the site.. With the rest of the ideas it would more than likely be you sitting behind your computer writing article after article to keep the site fresh and people coming back.
How do you make money, you say? Adsense might bring you a little bit, but check out Amazon's affiliate program. You can embed customized amazon ads, and even search tools, into your site. So say someone has a problem with there video card and they need a new one, they 1)have links right in front of them to help them find their new card, or 2)they can even search amazon directly from your site to find their new card. either way you get paid on the sale.