Building on Tip #4457, Multiple Fillet Radius Values, frequent tipster Kent Cooper has made a similar routine that works with AutoCAD's Chamfer command instead of Fillet. The commands C0, C1, C2....C9 can be defined for quick access to saved chamfer values.
Start by loading the AutoLISP file, then run any command Cx (where x is a number between 0 and 9). For example, you can run the command C2 and set the chamfer distance to 2.0. At that point forward until you might change it, the C2 command will execute a chamfer with both distances set to 2. The chamfer values you set for each Cx command are stored in environment variables so they will be saved in between drawing sessions.