Another New Bird

Yes another bird has landed in my window tree - and no I don't know what it is yet. My website of choice wasn't able to help me this time.

It was of medium size - bigger than a pigeon but smaller than a crow. It was shaped somewhere between a crow and a kookaburra. It had a glossy black hood that went down to the neck. The rest of it was a shimmering grey/silver.

Anybody have any ideas?

Yes I know I am becoming a bird watcher (and a not very good one) :-). I use the excuse (if I need one) that there are lots of 'new' birds on the east coast lol.