Disposing (every little bit of) SharePoint objects
Chris O'Brien has recently posted an article about proper disposal of SharePoint objects. While you might think that it's nothing else than yet another disposables article, Chris presents some extra insights on various pitfalls which you are likely to face while developing for SharePoint 2007.
Personally, I'm always trying to keep disposable objects within one method, so I can clean them up when not needed anymore. But then again, never say never: one day you might find yourself in a scenario when you cannot avoid it and Chris' article might just be the resource you'll be looking for.