I'm unaware if it's possible right now (we're in v25) or if anyone else has proposed it, but it'd be nice if we can have the grid markers visible on the boundaries of your active window when they get cut-off while panning/zooming in around the model. You could be in the Plan, section or elevation. as soon as you see a part of gridline, you'll see it's associated marker.
1. your grid markers are visible as normal.
2. your grid markers become ghosted into the plan (or section/elevation) as soon as you move around the model when they are no longer visible.
we've also been using gridlines as our boundary lines, so they appear in section/elevation view. but no grid markers are used. if a gridline is cut-off from the view but no markers are used, then no ghosted markers will be shown.
you can toggle this functionality in your Work Environment.
Liking this ghosting information idea. We're always needing to zoom back out to ID a grid line. Astronomy iPhone apps do this - displaying equatorial and ecliptic coordinate numbers at the edge of the screen.