Have you ever been in the position where you are trying to open a lock but it's too dark to see? I bet you have, which is why I made this Instructable. I cannot take credit for the original idea (see Yanko Design site: http://www.yankodesign.com/2010/04/21/never-miss-the-key-hole/ ) but I can take credit for the Sugru version of it! :)
Sugru (choose your color)
Small stick or pointed tool
Step 1: Plan Your Design
Take a look at your lock to decide how best to form a "V" around the keyhole. See the picture for a visualization (picture is of a different lock than the other photos).
Step 2: Form the "V" Shape Around the Keyhole
Take the Sugru out of its package and warm it up in your hands.
Form a "V"-like shape around the keyhole. The bottom of the "V" will most likely have to be flat so that the key will fit without obstruction. Try slanting the bottom part downwards a bit in order to give rainwater a way to run out without building up inside the lock (thanks Earthy Eric).
Use your hands, small stick, or other pointed tool to finish your design to your satisfaction. Be sure to try sticking the key into and out of the lock several times to make sure nothing is blocking the way.
Step 3: Finishing Touches
That's it, you are finished! Just wait the recommended 24 hours for the Sugru to completely cure.
If you are unhappy with the color of the Sugru, I would suggest painting it a different color--perhaps one that matches the color of the lock. Also, one could paint the Sugru with a glow-in-the-dark paint (thanks to Earthy Eric and to sillyzombie666).