I've dabbled in viola, saxophone, guitar, and ukulele and various times in my life. I didn't like saxophone but the others I enjoyed. The ukulele was most recent; since teaching myself guitar was difficult, and I didn't even have access to it at the time, I bought an entry level ukulele that had been set up for me already. It's so fun! More importantly its "friendly." The string action is low and they are softer than a guitars so they don't hurt my fingers, chord shapes are less complex than on a guitar, it's comparatively quiet (I share an apartment), and the sound is generally happy. All these things make it fun to just pick up and play and brightens my mood. Unfortunately I haven't played in a while since I got the to point where I had learned several chords, could play simple pop songs, but grew incredibly frustrated while attempting to learn finger picking. At this point I haven't picked it up in nearly a year; lessons would probably help. All that said, I think learning to play a proper drum kit would be so fun. Although, if rock band is any indication, that would be a long very steep hill to climb. Few things make me feel so hopelessly uncoordinated.
Cool! I hope to one day be able to dabble in an assortment of instruments!