If you're refering to Virtual memory, then no. Once you close/quit a program then that space used up is returned (both RAM & VM.) VM is simply a way of storing information which might otherwise have been stored in your RAM. (I have a utility which is supposed to clean up the use of ram & turbo charge selected programs but I have suspicions it doesn't really work! Which is why they decided to offer it for free after many complaints. lol )

As far as utilities that create temp files, generally if they are a responsible program they will have an option in their preferences which will give you an option for how long to keep temp files. This is generally used with programs such as video/multimedia converters, etc.) Most will delete these temp files after the end of the process or after quitting the program. Temp files being different to VM but has the same effect of using up space.

Part of an issue with LW for OSX using a lot of VM is as a result of OSX's Java. From what I've heard the new Tiger, OS 10.4 now has Java 1.5 & is more memory efficient. Also I believe the LW developers are working on this VM issue for the next release; ie: so Java doesn't use up quite as much VM space.