I found this neat css you can add to your `userContent.css` file in Camino or Firefox to hide that annoying invite box in Gmail.

		/* Hide GMail invites */
		span[class~=ilc][class~=sxs] {
			display: none !important;
		}
		div#nb_1 {
			display: none !important;
		}

If you use Camino, your `userContent.css` should be put in:

		~/Library/Application Support/Camino/chrome/

If you don't have one, just create a new one. If you use Firefox, your `userContent.css` should be put in:

		%AppData%\Mozilla\Firefox\Profiles\xxxxxxxx.default\chrome\

If you can't figure out how to do it in Firefox, check out this page.