I just noticed pdanet is now $23.95 for android (was $29.95). Seems like a good deal for tethering on the DROID. I've used the trial and it does a great job.
*edit:
- There are alternatives that allow you to tether for free but you need to root your phone (not for everyone)
- PdaNet trial is free for 30 days, then after that you can still continue to use it for free but w/o HTTPS
http://www.junefabrics.com/android/buy.php