At my current company we all eat lunch together (some bring their lunch, others eat out). It's not really a policy per-se but everyone seems to do it.
The only policy we have is of no eating lunch at desks so this gets us all in the same room.
We also have a "Results Only Work Environment" (http://www.gorowe.com) so you're free to do whatever you want, whenever you want, so if you want to get dry cleaning, walk the dog, catch a movie, etc. - you needn't do it over lunch. You can do it whenever.
With folks often out various parts of the day due to ROWE group lunch is sort of an encouragement for everyone to come together and socialize at least once a day.
We've been using it since we started earlier this year.
Changes that I like (from traditional companies):
* We're all treated like respectful adults. We're all trusted to manage our personal schedules to meet the expectations we set on an ongoing basis.
* No start and end time. Thus, I'm never "late" for anything. If I feel sleepy and need some extra rest, no big deal. If the subway is acting up, I don't have to panic and notify everyone I'll be "a few minutes late" (obviously if I have some obligations I've set with someone else, like a conf call at 10a or something, I'll have to make alternate arrangements).
* Every* meeting is optional (1:1s are not optional). No need to be dragged into things I don't want to do.
I can go to a doctors appointment, dentist, etc. without needing to take "sick time" or ask anyone. I try and schedule it outside of my "normal" working hours, as I like a core block of time to code, but if not, no big deal.
* I can run errands (pick up dry cleaning, meet HVAC repairman, etc.) any time of day without asking permission. OR anyone caring.
* No excuses for why stuff didn't get done. If we agree to get X done in an iteration, it's my job to make sure it gets done. If I decide to go to the beach all week and don't take "vacation" then I'm responsible for the work getting done.
* "Marginal" or folks not cutting it won't work out. If you can't meet expectations, you aren't doing your job, and appropriate penalties will apply. There's no place to hide.
Changes I'm still getting used to:
* Folks can work anywhere, whenever. So often I'm the only one in the office (I like to work at my desk - at home I have too many distractions).
* Pairing takes more effort. I have to make sure to schedule pairing sessions otherwise I'm not guaranteed someone will be sitting next to me when I get in the office.
* All communication needs to be async & recorded. Campfire, Basecamp, IM, email, etc. are used instead of face-to-face chat, as folks may not be here to hear it.
All summed up, I love it. I'd hate to work any other way.
The only policy we have is of no eating lunch at desks so this gets us all in the same room.
We also have a "Results Only Work Environment" (http://www.gorowe.com) so you're free to do whatever you want, whenever you want, so if you want to get dry cleaning, walk the dog, catch a movie, etc. - you needn't do it over lunch. You can do it whenever.
With folks often out various parts of the day due to ROWE group lunch is sort of an encouragement for everyone to come together and socialize at least once a day.