jQuery Chat UI Widget
I can't say there's anything technically wrong with doing it that way, and maybe some people who are only familiar with "self" in certain languages will get the point, but I think "this" is just as readable, and it saves you some code (along with some of us wondering where in the world "self" was defined if we're looking at a lot of code where the declaration isn't obvious).

So short of adding some extra work for yourself (and raising a couple of eyebrows), I don't see a big problem with it. Do you need it? No. Will it hurt? Not likely.