Thanks! I haven't seen these before.

Electrum looks interesting, due to simplicity. What does it mean by using a remote server though? Do they just use a single block chain remotely and tell you what your balance is for keys <a-z> ?

I'm not sure about the balance part, but I do know that they basically have the block chain on their server(s) and verified it's integrity. Still, now I have to trust some third party.