Recommendations for Small Combo Amp (5W & under)

Hello everyone,,,
I am looking for an amp for my office at work. Yes, I am lucky enough to have the luxury of playing a guitar in my office, during slow times. :D

So, I have been looking around for a SMALL combo amp. I am looking for some suggestions. Here are some of the things I am looking for:

1. Prefer 100% tube or at least tube based (like a Vox Valvetronix).

2. Needs to sound good at low, office volumes. Must be low wattage, so it can crank at low volume or have a attenuator.

3. No real price range or max. price, but the cheaper the better!

Okay... let's have the suggestions.