Environmentally friendly they are not, but there are advantages to physical PC meetings. Thursday and Friday is the PC meeting for ECOOP 2008. (I'm also on the PC.) By the good fortunate of being close to London, I managed to persuade William Cook to visit MSRC. It's been a fascinating three days - thanks for coming William!
In addition we have had Kathleen Fisher, Bob Gruber and Erez Petrank visit and give great talks. Yesterday, James Noble popped by and on Monday, Robbie Findler will visit and give a talk.
It pays to be close to Imperial!
(I'm looking forward to the ECOOP PC meeting - I'll post my impressions...)