I noticed that GMail likes to offer to "Invite to GMail" every time I post
to one of these mailing lists... I've almost invited on several occasions,
and I'm sure that spam would have been annoying.
If you want, the following line will add a custom filter for AdBlockPlus
users in Chrome and Firefox to prevent this from showing up; you may need
to restart the browser, though:
Christopher L Tubbs II