How can delete an orphaned temporary table on Mysql Innodb? I was issuing an alter table statement and suddenly the server crashed. Now I can not run any alter table command on that table, because it shows me error 1050, and says that a table named #sql1504d already exists.

How can I drop that InnoDB temporary table?
Go into the filesystem (DOS prompt, shell prompt, whatever) and delete (rm, whatever) any files starting with #sql

Also check to see how much free space exists on disk.  ALTER usually copies the entire table over.