I actually played a cripple once.
Altough that was in a political RPG using the GoT system, so he got around in carriages and stuff, being more of a spymaster anyhow.
Now, if it was dungeoneering game it would have been rather irrespesonsible of the party to take someone who can't even walk and isn't able to get around otherwise along anyway, so that point is moot.
The original Chad Thundercock
Great art btw