We are working with Roombooking System (see Fiza's link) to pilot SIMS integration. It is almost there and we are really pleased! The system is easy to work with, and integration will make it even easier! Our teacher's love it and it has really helped with booking ICT suites and resources like cameras, headphones, areas within larger rooms etc. Now we are adding meeting rooms, lecture theatres, netbooks, - everything that management initially said shouldn't go on the system!
(And no, I'm not getting paid to say that! )