The PGP web of trust is an interesting way to improve the trust you can put in a PGP key, hence in a signed resource (email, sourcecode). Basically, it can give you a reasonable confidence that the name of the author of the resource is not faked. Of course, don't forget that signed sourcecode might still contain backdoors, if the author was inclined to put some.
If you have uploaded your PGP key to the keyservers, and you had it signed by members of the web of trust, then you can verify that there are multiple trusted connections between your key and mine (0B56D613, Guillaume Cottenceau):
Note: input is your key id, of length 8, 16 or 32, optionally preceeded by 0x, in upper or lowercase, like FC243F3C, 0xfc243f3c.
Mon Jul 25 11:33:48 2005