I saw this posted by Speedrun Lover in August of 2007. It is an old trick, but is certainly easier to do than getting Nidoking to learn Recover.
1. Do the Old Man trick.
2. Fly (or Teleport) to Cinnabar Island, and use Surf.
3. If you keep a space in your name, you can catch a level 0 'M. Find one and catch it.
4. Now here's where it gets good. Teach 'M both Cut and Fly. Then give it a Rare Candy so that it grows one level. Upon growing one level, it evolves into Kangaskhan. Now you can teach it both Surf and Strength.
5. Congratulations. You now have a total HM user other than Mew.
Technically, this leaves out Flash (HM05).