I attended my local Hackerspace, Arch Reactor, in St. Louis, Missouri, tonight and the members were working with Sugru (self-setting rubber). Several minutes after I walked in the door, the nose piece of my glasses broke off.
Since I needed to drive myself home and see comfortably during the rest of my night, I decided to use a bit of the Sugru to fix my glasses. The positive results mean that I will be able to continue wearing my glasses until I can order a new pair.
Clean the rim of the glasses where the pads will be located with an alcohol soaked cloth.
Remove a small portion of Sugru from the package. Roll it into a ball, then into a small cylinder. Press the cylinder against the edge of the glasses where it will meet your nose. Repeat for the other side.
Press your glasses lightly onto your nose. If you can see the nose piece while wearing the glasses, remove a small portion of the Sugru and restart the process. Check your look in the mirror and ask the opinion of others around you. Make sure your glasses sit level on your face and are not too close to your eyes. Eventually you will have nose pieces that will comfortably hold your glasses on your face while leaving your glasses looking somewhat normal. Once you have them molded to your liking, allow them to cure overnight.
Edit: After 11 months, the Sugru nose pads on my eyeglasses are still working very well. I did have an issue where the Sugru would fall off while cleaning the glasses. I had to use a bit of Super Glue to re-attach them to the rim. Caution: Be sure to allow time for the Super Glue to dry completely before placing the glasses back onto your face. You may want to consider using a more "face friendly" glue.