24 hour clock times in 0745 format

I like to express times in 24 hour clock format, but without a : or . in between. Surely I can't be alone in this? So long as the user types "at" before the time, could Sandy not start recognising times like 0900 and 2100? I don't think that's too ambiguous, and it would stop me accidentally scheduling all my reminders for the beginning of the day (i.e. 0700 digest).