Search for a projector

I have recently been given the task of surveying and buying a projector for a society I am in. The budget is not much - just £300 and I would be really happy if anyone could give me some suggestions.

I was really keen on the new breed of small and highly portable pico projectors. However, I discovered that their biggest disadvantage is their brightness which are only about 10-100 Lumens. According to one of my Twitter friends, I should go for a minimum of 2000 Ansi Lumens as below that the image may not be clear.

Would really appreciate any suggestions and tips.

Thanks.