Yes, I would think we'd need about 20 people to have a room - otherwise we might look a bit sad.
Karaoke would be a great idea! I love Karaoke - especially when drunk!
I'll see if I can get a drug company to sponsor the room - we get pharmaceutical reps in all the time and they are often cool with sponsoring bits and bobs. We'd just have to have some balloons or pens with Xenical or whatever on to justify them paying for it.