Good to mix it up occasionally, get dat' dere' explosive pump. One of my favourites is for Bis - Buddy curls (BB or CB) (or if like me you don't have a training partner just wait the amount of time it took you to complete the last set, use the lap timer on your phone)...
Pick a fairly light weight, and do..

3 x 10 (30 reps)
3 x 8 (24 reps)
3 x 6 (18 reps)
3 x 4 (12 reps)
3 x 2 (6 reps)
1 x 10 (10 reps)

100 reps total. As you get into the lower rep sets the rest period decreases also. Give it a crack.