Check out the rather brilliant-looking, Lego-compatible Nimuno Loops:
Imagine being able to build around corners, on curved surfaces, or even onto the sides of that sailing ship you’ve just spent hours building. You forgot to engineer a point of attachment for that sweet dinosaur-smashing cannon? No problem. Snip a length of Nimuno Loops, stick it on the hull, mount your cannon and be on yarr way.
[YouTube] [Via Beth Allen]
Why didn’t I think of that years ago?