I couldn't find an appropriate existing thread for this (and was shot down in "Database Error Thread"):http://www.penny-arcade.com/comic/1999/10/25/
is part of the back/next sequence, but clearly says it shouldn't be.
Also, I'm not sure if double-comics for the same date are considered an error, but I have a lot of examples of pages like this:http://www.penny-arcade.com/comic/1999/10/22/
If there's a better place to report problems like this, let me know. I happen to run across plenty of them while maintaining an unofficial PA search engine.
Check out our new sister Android app for PATV
I think alpha said at some point that he was redoing the archive along with another site redesign. Can't say I know the progress of that at the present time.
Allow me to complement you on the search engine, though! I even have it in my Firefox search bar.
SE++ Forum Battle Archive
Thanks for the compliment on our site! If you have any ideas of how to make it even better, let us know!