Ale
I just fermented an IPA (Bell's Two-Hearted clone) at 55. The IPA yeast was Wyeast 1272 American Ale II.
I suspect many / most ale yeasts will ferment at that temp, especially if you pitch a lot of healthy active yeast.
Hybrid
I've also got an altbier finishing at 55. The altbier had yeast straight from the brewery, but was probably the same as Wyeast Dusseldorf Altbier strain.
A steam beer is also a good choice.
Lager
Of course, all lager yeasts will ferment happily at that temp. If you're looking for a beer recommendation, an octoberfest is delicious this time of year (hint: they are good even if they haven't been lagered for 6 months). Maibocks are also good lagers. And a schwarzbier is a fun winter lager.