I too have a warning on hammie danger.  Sharp claws (even those sharpened
from a recent clipping) can catch on most any hammie.  Merlin dislocated
his toe last night by getting his nail caught in his fuzzy-floor hammie;
he left the hammie and got on the shelf below, but his foot didn't
follow...
 
Be careful little fur kids; even sleeping can be dangerous at times!
[Posted in FML issue 3941]