The other day I built me a headphone amp to practice guitar without stressing the GF and neighbours.
It's just a minimal 386 based amp with input volume knob and low-cut switch. Used a basic ABS enclosure for it and screwed Breket's (a local handbuilt valve amp company I am kind of involved with) laser cut logo on it, since it fit the enclosure quite nicely. Still need to find a nice pot knob on it, used one from the parts bin for now.
(http://i.imgur.com/uEdwWWil.jpg) (http://imgur.com/uEdwWWi)