I read that Paul Stanley's guitar tech used this stuff called "Gorgomyte" to clean Paul's frets and fretboards.  I had never heard of it.  Of course I found a seller of the product on Ebay and gave it a try.

It's great!  Gorgomyte is a cloth that is impregnated with chemicals that will clean your frets and leave a shine on your fretboard.  A small 2" by 2" square will do an entire board and a package comes with enough of the cloth to do 20 boards.  I removed the strings from my Iceman and followed the instructions.  I worked the small square from the first fret to the 22nd rubbing each fret wire and working the Gorgomyte into the space between the fret and the board.  I always wipe down the fretboard after playing, but this square was BLACK with dirt after only a few frets were done.  After cleaning with the Gorgomyte you have to wipe down the board with a clean cotton cloth to bring out the shine.  The neck looked killer.  I restrung and had at it.

The neck felt smoother than before and it certainly looked better.  The board felt much better than the usual lemon oil treatment.  It still felt and looked great after a few days of rehearsal.  I will treat all of my guitar necks with Gorgomyte when I restring from now on. 

GHS is distributing this so it should be easier to obtain.  Try one package on a guitar and see what you think.