I don't know if you have a GFC700 to go with it or not.
You can fly a steep approach from a higher than published altitude. Then past the marker use VS and catch the glideslope from above. Useful when penetrating icing layers.
Use VNAV to fly the approach step-downs
Create a manual waypoint at an altitude restriction, class B ring for example. Then use VNAV to hit the altitude right on the ring.
As mentioned OBS, I use it in the mountains to create airways where none exist. This might be really important in a VFR into IMC emergency for example.
Airways, one of the big advantages over the 430/530 IMO.
Flight path marker. Love it. 25 Knot gusting crosswind combine the Flight Path Marker with SVT. Hold the FPM on the runway and fly a perfect descent.
Go around button. As soon as you miss, throttle forward and hit the go around, G1000 goes off suspend and cycles to the missed and you can follow the FD.
Strange multi-runway airport on a visual or anytime at night? Load an approach for the runway you are assigned and select VTF, then use the MFD as a backup visual reference to make sure you are lined up correctly. Not just a G1000 thing, but the big MFD makes it more usable.