We've started enforcing limitations on pictures used in sigs and avatars in terms of bytes, as some users were using pictures of several megabytes, and making every thread they post in load slower than a one-legged turtle on a heroin overdose.

All avatars and sigpics over the limit were replaced as a result of this.

The limits are as follows.

Avatars - 60kb (Standard)
Avatars - 100Kb (VIP)
Sigpics - 350Kb

On a related and somewhat funny note, people who were ducked in the avvy include:
Gum
SlipAnc
Hampa
BenDover