I cannot believe I locked myself out of my blog ... on my own server.
The funny thing is how, really. Every time I tried to login it said it didn't know who I was. Without being able to login, I couldn't look at the log to see what was wrong. It was never important, so I just left it be for a while.
Well, now I'm trying to prepare all the sites for the move to Drupal 5.0 and I'm stripping out unused modules so I know what bare minimum each site's going to need, etc. and I got tired of leaving this site alone and looked into it. Well, it turns out there was a collation problem in the users table where the table was set for UTF8 and the columns were set to ... somehow ... latin1-sweedish. Yeah, bork bork.
PHPMyAdmin to the rescue (by manually reading the watchdog table and altering the users table) and now it works. I cannot believe I let it go this long...