There was a Crystal Mew and a CrystalMew.

Also back in 2002 when we switched from UBB to vB (with the EZboard being during that limbo), since UBB let people change their displayed names but vB didn't - people got temporarily stuck with whatever names they had. Mod positions, however, did not carry over and had to be reassigned.
This lead to a bit of a pickle involving Vaporeon911 who was using the name "SmoothCriminal" on the UBB and I guess there was another unrelated "SmoothCriminal" post-transfer completely unrelated who they accidentally remodded instead.