I love messing with tunings.
+1
My favourite at the moment is CGCGGE / CGCGGEb as suggested by a friend to have the option of playing minor chords. Unfortunately the guitar I have in this tunning is currently a mess wiring-wise, so no play with this tunning right now :(
I have also started playing with shifting pitch with the standard tunning. First I did it with my acoustic guitars. My Freshman is tuned in standard C and when I get back to my parents place, where the guitar lives, for Christmas, it is always a joy. The guitar has such a good projection, with the low tuning it's creating a good vibe :)
Done a similar thing with the Tele, but going up to F, as the low "E" string sounded flabby and dull, tuned in E, in comparison to the other strings. It seemed to work but now that the strings have loosen a bit more it is giving me a flabby F... I tried in the past to tune it in drop D to overcome the problem of the flabby 6th string, and it kind of worked, but I 'd quite like to be able to play the Tele in standard tuning and enjoy playing all the string. A bit of a pain at the moment.