andrew,
are u sure that u want to force the user into entering
some 'strange' keystroke combination? why not have them
enter number in plane ole scientific notation such as;
3.1416e2 (for 314.16) or 3.1416x2 (pi squared).. of course
i dont know who u users are, but Keep I Simple & Stupid is
the best rule ever made for programming anything for anybody.

>>>>I need to be able to provide users with the ability to enter
>>>>scientific expressions into fields eg 30^0C.
>>>>