Looks promising.
Although I had to actually look at the code to figure out what it does. You may want to write up a description for it.
Also, your function names and variables should use a prefix that identify them as unique. It will prevent them from clashing with other plugins and causing unexpected damage. perhaps adding j20_
to the function and global variable names. Refer to the Codex coding standards and developer docs.
Otherwise, it looks cool. Keep up the good work.