If you are a Delphi developer and are not using the full FastMM memory manager (either the free version 4 or the commercial version 5) you really should try it. The limited FastMM version, that is included with Delphi since Delphi 2006, does not have the full debug mode. And that’s the mode you should be using while you are testing your program.
Why am I recommending this so strongly now? It has found a really nasty bug in the code one of our core modules which accessed memory after it had already been freed. It took me ages to actually find the problem even after I had been made aware of it. Be aware that running in full debug mode can have a huge performance impact, so you should definitely not ship that code.
If you don’t know about FastMM, watch Jim McKeith’s Webinar Essential Delphi: FastMM or read the blog post Detecting Memory Leaks in Delphi applications using FastMM 4 by Alexandre Machado.