Well, it's cheap Behringer electric guitar recorded and made into Sounfont (SF2) file. It's free, public domain, size is 19.5 MB.
It's not a great thing by itself, and there are some slightly detuned samples, but all in all, it works great for me. Or, at least, when I use VSTs of [u]virtual amps[/u], I get a better sound with this SF2 than with other ones I've got on the web; I suppose it's the tone of it, very muddy and cheap and gritty and real. No velocity mapping, because I'm lazy.
Download: Behringer Electric Guitar Soundfont