Millenium Park is a complex, situated close to the Hilton Apartments, in Colombo. Most bajaj drivers should know where it is if you ask them to take you there. It consists of a number of small food outlets, selling a wide variety of food, a covered eating area, a pub, a 10 pin bowling alley, a cafe and I believe a number of other activities like laser quest.
I have eaten at a number of the food outlets and have enjoyed them all. The food is basic and cheap but the service is quick and the portions ample. I have been to the pub too (of course) and it is one of the better ones in Colombo. They have a big screen that plays either movies or sports events but you can sit so that this doesn't distract you if you want. They do food including some rather nice nibbles like hot cashew nuts.
The bowling alley is where we frequest the most. We try and get down there every Sunday. However, at the moment they are having a lot of trouble with the automated system that puts the pins back into place. Last Sunday we had to move lanes mid way through a game due to technical problems and we had to call for assistance at least half a dozen other times over the course of 3 games. I use that as an excuse for breaking my concentration as my scores of 104, 102 & 112 were pretty dire. Hopefully they will have it fixed by next weekend. It costs 200 rupees a game (on a Sunday morning at least). The bowling alley also has its own bar.