We believe the culprit is a bot. It is replacing a large section of the Main Page with links and spam. I know you want to help, and I know you're well meaning, but if you help in the wrong way, you're going to cause (minor) problems.
Please note: it is REPLACING. That means Editing out the spam will delete sections of the Main Page. If you are trying to help, do not Edit the page. Instead, go to the History Tab of the Main Page and find the top entry. Hit the 'Undo' link on the far right. Next, check the change. Ensure the fix puts the Purpose section back.
This page was created by Rob and contains legalese necessary to protect himself. If your help deletes that, you're hurting Rob. If you don't know exactly what you're doing, then don't try to help. There are several of us that do know, and will ensure everything goes back to normal. Just wait a few minutes: we've got the page on Watch, and we'll get to it ASAP.
Note that if you help, the following sections should be present:
=Making Stuff Up=
=Where to Start=
If any of these sections are not present after your help, just relax. We'll fix it. It's just a matter of hitting the right Undo's in the right order, so it's not a big deal. If you panic and try to fix it, you might make things far worse.
The solution will eventually have to be some sort of security, but we have to get Rob to notice what's happening first. this only started last night, so please be patient while we try to get this stopped.