Are you still creating Functional Globals (a.k.a. LV2-style globals) that look like this?
If you're programming in LabVIEW 8.5 or later, do this instead!
In LabVIEW 8.5, Feedback Nodes gained the ability to live on the top level diagram of a VI... no loop required. This feature gives us the identical functionality of a single-iteration loop with an uninitialized shift register. And let's be honest here...the uninitialized shift register on a single-iteration loop is kind of a hack.
Not only does the Feedback Node clean up our diagrams, but it is slightly faster (sometimes by about 5-10%) than a loop with an uninitialized shift register. This is largely due to the removal of loop overhead.
So get over your Feedback Node (and backwards wire) hangups like I did and make your functional globals more efficient!