Bird,
I usually just boil rutabagas and mash them with butter and salt, though I'm sure there are probably lots of ways to cook them. They taste a lot like good turnips, but are a bit sweet even without adding any sugar. My mom always used to add just a pinch of sugar to turnips as a seasoning, but with rutabagas it's not necessary. They're denser than turnips, too. I start craving them when the weather starts getting cold. Most of the local stores have them at least part of the time, though usually just a few at a time. I buy them at WalMart because they have them for .50/lb and that's about as cheap as you can find them....cheaper than turnips locally. Remember when turnips were what I guess I'd call "poor folks food", like beans and cornbread? We used to get them for next to nothing back home in Tennessee, and ate them (and beans and cornbread) pretty often while I was growing up. Now a small bunch, maybe 3-4 small turnips, is $1.50 at WalMart. And I saw Tyler Florence making a turnip puree on the Food Channel the other day. And of course grits are now served in fancy ways, too.
Chuck