Funny Ukemi
Hyper-ukemi:
        the art of getting thrown so violently that you almost roll
        multiple times in succession before rising to your feet, or
        rise to your feet so quickly that you still have a lot of forward
      momentum, and thus sort of stumble off until you can apply the brakes.
Thump-ukemi:
      the art of rolling perfectly straight, and perfectly round.
 ...and then realizing that you estimated the ground to be about a foot
      higher than it actually is. *thump*
Wrong-technique,bozo!-ukemi:
      the art of making the most beautiful rolls you've ever made...
 ...when you're not really supposed to roll at all. [ This has the
        added side effect of that it usually surprises tori so much that they 
        let
      go of you, and you get away without injury! ]
Wobbly-ukemi:
        the art of taking the advice of people who are only slightly higher
        than you in rank, resulting in you trying out a different approach to
        rolling, resulting in you spontaneously rolling in a direction which is
        not "forwards". This has the added advantage of causing you 
        to bump into
      other people, esp. when practicing ukemi exercises in lines.
Accidental-ukemi:
        the art of falling down with so much force, you end up awkwardly rolling
        backwards over yourself anyhow, not unlike one of those desktop dodo
      birds that drinks from a glass.