It's the ultimate present for any guitar player with a love of beer (pretty much every single one then...)
Hesslerk (opens in new tab), a DIY amp maker from Chicago, has created the 20 watt Heineken Beer Keg amp. Plugging into a standard wall outlet the amp is pretty simple when it comes to knobs and features - it has a power switch and volume control.
The site says it works great not only with guitar, but bass and MP3 players as well. It only costs around £60 too, but there is a two week wait due to demand.