Enter Ankie of WoW Ladies, with an intriguing idea to support the guild's website.
They have a little meta-game going, where every time you do something to contribute to the resource, you earn points, which are then redeemed for items from the guild bank. Put in a bio, get some points, redeem them for a guild bank enchant or a vanity pet. In essence, they're rewarding activity on the guild's site with little guild-related bonuses in the game, building a nice community in both places.
Obviously, that might not be feasible for all guilds, and certainly you can make your own tweaks (maybe you want to run a contest for one specific thing instead). But to those of you out there who've found a good way to build community in your guild (for the rest of us who have lots of resources that aren't getting used), what other ways have you found to connect your guildies outside the game?