Firefox bullshit removal
Due to the incessant swarm of complete and utter nonsense that has been forcing its way into Firefox over time, I've decided to start collecting my personal list of “must-have” about:config tweaks required to turn Firefox into a functional brower.
NOTE: Unfortunately this is somewhat out of date. The comments link to some resources that may be more up-to-date. Patches welcome.
WebSockets
These can be used for nefarious purposes and to bypass access restrictions.