I use aCME UF 8 & UF 5. They are chineese, but amazing value. usb keyboards
with complete linux/alsa support. A CME UF5 is a 4 octave keyboard tho and i
think the smallest; but if feels much better than those 2 octave controllers
mentioned and has a complete control panel full of sliders/knobs etc. Pity I
can't get the transport controls to work !