Anybody who ever has the need to desolder things, do yourself a favor and get one of these. You also get an excellent iron with temp control that heats up instantly.
Unless you don't value your time. In that case you can play around with copper braid and spring-loaded plungers to your heart's content.
@wdormann I had one (ZD-985) and I gave it away to switch back to a good manual pump (Engineer SS-02).
It didn't really work on 6 traces boards, and the unyieldy shape makes it easy to apply too much pressure and damage pads... That and limited desk space.