Is there a way of increasing memory in Indesign CS6?
Legitimate out of memory errors are pretty rare for ID. In more than ten years I don't think I've ever seen one myself, and most of the ones that are reported here are caused by some sort of document problem.
What's the OS? What version of ID (including patch level)? What are you doing when you see this error? How large are the files? Do they contain lots of native or pasted vector material instead of linked vectors?
How much free space is on your hard drive?
I know there is no way to add memory for the app, but I will say I have the same issue: new iMac, 16gb ram, 1tb drive, Mt lion, all of everything patched to the top, still reports out of memory anytime i export to pdf or run my preflight pref.
Otherwise everything else is fine. Killed off pref's, wiped ID caches and font caches.
I think the app has a memory leak personally when it comes time for those 2 calls to be invoked.