I'm a qualified historical researcher, and do quite a lot of voluntary work for e.g. local museums/art galleries, etc. I enjoy it. It gets me to meet a lot of interesting people. This evening, for example, I attended a function for about 120 people, and got to chat for about 20 minutes with the world's leading authority in her field. Most importantly for any retired person, it keeps me mentally fresh and sharp. I agree with Blind Corner (#40) that retirement is the "greatest thing ever". It beats the hell out of working my balls off to earn somebody else a Merc. That's for sure.