I just wrote a little utility called "numergrate" (short for numerate
migration files). I think it can be useful for a lot people who are
using Rails to move migration files around. You can do ruby script/
numergate 50 before 30 to move migration file #50 to position 29. The
utility is also integrated with subversion via the svn client.
Please give it a shot and let me know if you have any comments or
suggestion. The URL is http://alexle.net/archives/206