A colleague at Penn State pointed out this little nugget to me a few weeks ago. Apparently you can supply map data to Google Maps to make their map more accurate using the Google Base Map Partner Program. So you could supply Google with locations of important landmarks on campus, bicycle paths or your sidewalks. Think of a user using your mobile-optimized campus map and being able to get directions along your campus sidewalks from their current location to a particular building for class. Now you could try to code that yourself but it makes more sense to make it available to Google so everyone, even those not using your mobile solution, can take advantage of the data.
If you want to supply your data here are the formats that Google accepts. The only school I know of that has this is UCSB [example]. If you have experience with the Google Base Map Partner Program please drop a line in the comments.
Update as of May 23, 2011: I wrote another blog post about Google Map Maker which might also prove useful for adding your campus sidewalks to Google Maps as well.