Wording is important when you're writing a letter, especially if you're trying to carefully word a request. If you're looking for financial relief or forgiveness, I have new hardship letters and apology letters. If you simply want to thank someone, there are plenty of new thank you letters.
If you're looking for clemency instead of a loan, head over and check out the etters for misbehavior, social slights, workplace issues and personal apologies. The new forms can help atone for troublesome or delinquent behavior at work, school or in the community. These include apologies for graffiti, interruptions, tardiness, and violent behavior. I advise using these as launch points to give you ideas for more personal, specific apologies.