In reply to Bulley: I've lived in Southampton/Winchester area for a few years, and I split my time between Calshot, Craggy and Fort Purbrook.
Calshot is freezing in the winter, the routes never change, and the bouldering is a bit crap. Plus it's not uncommon to queue for 20 minutes to get in. On the other hand, it's reasonably close and a bit cheaper than craggy.
Craggy's good, but the most expensive of the 3 and about 1-1.5 hours drive, depending on traffic.
Fort Purbrook is what it is; quite small, all bouldering, cheapish (£4.50) and easy to get to (straight down the M27). It's not the most inspiring place, but I still visit quite regularly.