I see that now everyone has clickable signatures that lead you to their homes, how do I do this? Thanks!

I just tried it, it already does. Usually the person making the siggy add's it, but you go to the user control panel right above your head on this page then go to profile then click on edit signature. Now you copy your apartment key and paste it in the edit signature box then hit submit. Hope that helped, here is where your siggy took me....