I have worked with several big databases and the names of stored procedures were very different:
SP_PrefixXXX
PrefixYyyXxx
Prefix: Rep, Act
I tend to try to give names that not only give an idea what the function is for, but what the input variables will be.
For example: ProcessMathEquationWithFieldIdPlantId
This will help give information immediately to anyone else using it, I believe.
I also avoid sp_ and usp_ to limit any chance of name collisions.