The first five rules are pretty good:

1. When in doubt, don't have one.
2. Everyone now knows precisely what time it is. Show up ten seconds early; one minute late is too late.
3. 10 minutes is the maximum length of a conference call. In, out, over.
4. If the meeting is only ten minutes long, good news, you have time to pull over, time to let the dog out, and time to give us your undivided attention.
5. If you're not planning on speaking, no need to attend.