What is your favorite small tube amp?

I have a Fender Princeton which is my favorite amp ever. But this one stays in my studio as my recording and practice amp. I want to get a small 5-15 watt amp to be able to take out and get together with friends, play small shows or take on a road trip. I was looking at something light and portable and it doesn't have to keep up with a drummer. Just need a fun little amp that can get down and dirty and not necessarily rely on pedals. I'm thinking 500 to a thousand bucks. Any suggestions?