Back from hiatus.
I've never had an excuse to do remote debugging until recently, but I've always heard that it's a serious pain in the ***, hence, I avoided it. Recently I really needed it to work, and of course, it didn't.
Remote debugging seems to be a little easier than it used to be, and if you do enough searching you'll eventually find what you need. Here's the short version:
Step 1: Go here: http://www.microsoft.com/downloads/details.aspx?FamilyID=440ec902-3260-4cdc-b11a-6a9070a2aaab&displaylang=en
This is the remote debugging service installer. Assuming that you don't want a full Visual Studio installation on the remote machine, you can install this service on the remote machine.
Step 2: Add permissions. The debugger service you downloaded in step 1 needs to run under an account that has permission to your local machine. I think it may need admin rights on both boxes, but I'm not sure. In any case, the accounts I used to get it to work were admins on the machines they were on.
Step 2.5: Fake it out. Here's where it got wonky for me. I couldn't add the permissions in step 2. My dev box was in one domain, the box being debugged was in another domain (dev domain), and the domains did not have a trust relationship. Therefore, I couldn't add my local account to the dev box, nor could I add the remote account to my local box. Game over? not quite. There is a workaround. Create a local account on your dev box with the same username/password as your domain account. Do the same on the remote box. Run the service as that account. Magically, it all just works.
Step 3: Miscellaneous debris. I also was not able to resolve the remote machine's name through DNS, but when you connect to the service, it wants to resolve the name. Get around this by adding the remote machine's name to your hosts file (at c:\windows\system32\drivers\etc\hosts). It just works better.
Step 4: Do it. Select Debug->Attach To Process. Under Qualifier Type the remote machine's name (or IP address) or select Browse, if you have name resolution. The processes from the other machine should show up. Select the one you want. (Don't forget to set a breakpoint).
That's it. Easy when you know how. Serious pain when you don't.