So, fear of losing that tiny plastic cap that "protects" your Mabooks MagSafe? Here are simple steps.
1- thick needle or sharp point of any kind (use a needle like point, that is, not the same diameter but thin at the start and thicker at the base)
1- 5cm or longer nylon cord
Step 1: Punch the cap
Use the needle or sharp point to punch at the center of the cap.
Step 2: Make a nod
Take the nylon cord at one end and tie a nod, make at least 2 nods in the same end.
Step 3: Insert the nylon cord
Use the other end of the cord (the one without the nod) and insert it through the hole you punched in the cap.
Step 4: Tie the second nod
Tie a set of two consecutive nods to fix the position of the nylon and the cap as shown.
Step 5: Tie the opposite end to the MagSafe and you are done!
Presto! Never lose your little cap anymore (they don't sell this at the Apple Store or eBay!).