Right now my gaming rig isn't getting to much attention and I decided to forsake it for more space in my tiny efficiency apartment.

I plan to get rid of my HDTV and entertainment system (I rarely watch TV on my TV anymore, netflix and hulu are great) and get rid of my huge gaming rig (Coolermaster HAF X, rather large) and just keep my computer desk, Xbox 360, and my monitor.

However, I do need a computer, and I was thinking about trying to build one that is rather small.

-Could anyone recommend me a small case? I'm looking at http://www.newegg.com/Product/Product.aspx?Item=N82E16811108065, but I don't have much experience with them. My biggest concern is heat management and space (planning to put a wireless card in it)

-How powerful is the Llano 3850? I mostly plan to stream 1080p videos and the ocassional flash game, I have little knowledge about onboard video, so it would be helpful. Also, is the 300W power supply in the above case sufficient enough to run this cpu, an ssd, and a wireless card?

-Any other things I should be concerned about?

http://www.youtube.com/watch?v=3h77el9JOAs&feature=plcp

That looks great, but I'd rather not spend that much on a case, is the one I suggested good enough at distributing heat? (I'm not doing anything to intensive, but I like to have the room temperature up in these cold Alaska winters.)

My only other major concern is the PSU, I'm not great at calculating how much power I need and am wondering if I should get a separate PSU.

So far I'm thinking of running an A8-3850, 8GBs of ram, and a 240GB SSD.

With smaller space the (lack of) heat is of much more importance since there won't be a lot of room for air and cooling, so I recommend you look for energy efficient parts rather than powerful parts, like the Intel Core i3-3225 with a TDP of 55W (a bit high still but reasonable). And yeah, 300W is plenty. My computer consume around 200W during full power.

EDIT: The A8-3850 isn't really that energy efficient, having a TDP of 100W.

The advantage of getting a different PSU, though, is for the reasons you mentioned: getting an energy-efficient PSU. I doubt highly the one in that case is 80+ certified, for example, and may even be an active contributor to heat itself.

Though I'd note you can get small form factor PC cases with amazing cooling. The Lian-Li I linked to was designed to house a full gaming GPU without melting, for example (obviously costs more, though)

True, I upgraded to a 80+ Gold PSU last year and I'm extremely pleased with it. Very cool and nice, even if you touch it after being on for months you still could mistaken it for being off, no heat at all.