PHPUK, the conference organised by the PHP London usergroup is being held on Friday 25th February 2011. If you haven't bought your ticket yet, then you should!
I'll be there talking about optimising a Zend Framework application, which should be interesting. I'm going to be looking at what's slow in the ZF code itself and have been profiling using xhprof which is the first time I've used it. It's quite good, once you have it set up :)
If you are going, then come and say hello.