Bird Baths for Winter

This spring we put out our first bird baths and have enjoyed seeing the birds use them. We'd like to continue through the winter if possible. From what I understand the water would be used more for drinking rather than bathing in when the temperatures drop. We do get pretty cold, dropping to -25F at times. Could you give me some ideas on what brands/types might work best?

Thank you so much.

Hi Chilly, Here is the one I bought a few years ago and I really like it.

http://www.ebay.com/itm/ALLIED-KOZY-BIRD-SPA-HEATED-BIRD-BATH-PEDISTAL-/370097103382?pt=LH_DefaultDomain_0&hash=item562b81a216#ht_4178wt_1398

I use a heated dog bowl dish for the winter months. I put a rock in it, for the small birds to land on. Something like this one. http://www.drsfostersmith.com/product/prod_display.cfm?pcatid=1277

We also use an electric heated dog dish- we have used the same one for more than 10 years and it still works! I couldn't find a picture of it so I just attached a nice winter shot of my "thinking seat" in the shade garden-needless to say it gets more use in the other seasons!! MW