If you enjoy making chiptunes (music created from video game sound boards and MIDI files) you might want to take the plunge on this synthesizer that looks like an arcade stick. It's call the Pianocade and it's a fully-customizable synth built around the Nintendo Entertainment System and Game Boy hardware.

The developers at Portmanteau Devices are currently taking pre-orders, with prices starting at $100 for just the electronic compontents and going up to $325 for a two-octave stick. You could get a MIDI controller or a much smaller, programmable synthesizer at that price, but it wouldn't look nearly as cool.

The Korg mini synth I've lusted after for years now is about $400 and I would just use it to run chiptune sounds anyway. Pianocade is even open source, so you could probably get the same use out of it as the Korg if you wanted to try. 

The real downside to the Pianocade is that it currently isn't compatible as an arcade stick, but Portmanteau is looking into adding that functionality before launch. Imagine rolling up to a Fighting game competition with this behemoth.