My limited understanding was that the microwave stats ruled out a closed universe of any topology. But I could be wrong.

Have you got a reference? I'm annoyed to have completely missed a result of this import...

Okay, I'm obviously not an astrophysicist, and my knowledge of this stuff is far from expansive, so I may be (read: ``probably am'') misinterpreting this, but, from http://www.discover.com/mar_01/featdark.html:

Recent studies of microwave background radiation had hinted that the universe is flat. But last spring, data from balloon-borne instruments lofted over Texas and Antarctica supplied convincing evidence. Minute fluctuations in the radiation were the expected size. The most precise measurements available revealed that the shape of the universe is flat; it has the critical density and omega equals one.

My understanding is that the universe would have to be closed for it to be finite. Then again, my understanding is that would imply a spheroid universe, yet I've also heard theories of a toroidal or moebius-like universe. I don't know how to rectify all that information. Regardless, I'm pretty sure that flat is flat. But I could be wrong.

Also check out the press release for the balloon experiment mentioned, MAXIMA. Apparently there was another one called BOOMERANG, too.