I was just trying to get the signature that I use for other sites to work here and I noticed that the restriction is 500 characters total (including BBCode). I just wanted to make the suggestion that it be based on actual displayed characters. At SitePoint, I believe it is 65 characters per line for 4 lines. Just to give you an idea what my signature usually looks like:
Patrick O'Keefe - iFroggy Network | Articles: SP - WDR
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Anyway, just a suggestion, thanks.