We've been seeing loads of these recently, not as a result of memory leaks (the usual suspects) but the result of trying to do too much at one time. Now that 64-bit operating systems are here, couldn't we take advantage of the extra virtual address space? Microsoft have a comparison of 32-bit and 64-bit memory architecture for 64-bit editions of Windows XP and Windows Server 2003
outlining the changes between the two memory architectures. Next step is to see whether the 64-bit operating systems are approved.