Two great fretting hand exercises I used to do:
1) Place the fingers on the top 4 strings on consecutive frets, i.e. 1st finger on 9th fret of the high E, 2nd finger on 10th fret of the B, 3rd finger on 11th fret of the G, 4th finger on 12th fret of the D. Always keeping all other fingers on the notes, move the 1st finger down a fret, then the 2nd finger down a fret, then the 3rd and 4th until you have the original shape but one fret down. Sound the chord at each step to make sure all notes are fingered properly. Work your way down the fretboard like this. It gets progressively harder but is great for strength and dexterity.
2) Place the fingers on 4 consecutive frets of the same string. Start with the A string. While keeping the 3rd and 4th fingers on the string, alternative the 1st and 2nd fingers between the next highest and lowest strings, then switch them (so they're skipping back and forth over the original string). Sound the notes at each step. Expand the width of the movement by moving one string further each time, i.e. the next string up and the next string down (where there is one). By the end, the fingers will be alternating over the full width of the fretboard while the other two remain pressed down. Try it on different strings, with different pairs of fingers, always holding the unused fingers down. This is an amazing exercise for finger independence and dexterity.
3) Take a double page of a broadsheet newspaper in one hand and crush it into a ball. Repeat with other hand. Excellent strength/grip exercise.