im suprised no one has mentioned hammers......... if you slow the movement down and dont jerk the weight up as most do, they are a good finisher for your bicep routine with out having to directly work forearms
I love, love, love
DB hammers, especially the way I do them.
I'll start standing against a wall, with my footsies about three feet in front of me, and try to keep my elbows pinned to the wall at all times. I'll initiate a training cycle with something I can get 10-12 very strict reps with: explosive on the way up, hold at the top for a second or two, then back down at a slow, smooth tempo (probably avg. 3-4 sec./rep). Every rep is initiated from a dead-stop, and I do both arms at a time.
When I reach failure that way, I'll put the DBs down, shake my hands out, take a few very deep breaths and then do regular DB hammers. It's still strict, but if my elbows move a little that's OK. I might get 3-5 more reps that way.
Then the fun starts. After setting them down one more time, shaking my hands out and a few more deep breaths, I pick them back up and do alternate hammers. At this point, I'm still trying to hold for a brief squeeze at the top, but I use an increasing amount of English on each rep. In short order, you might find you can squeeze out another 20+ reps/arm this way; it all depends on how light your super-strict miniset poundage was, of course.
As I get further into a training cycle, I keep increasing the weight until I'm down to as few as 4-5 reps on the most strict portion of the set, and I'm very lucky to get 20 total reps/arm. I've never gone heavier, partly because I tend to get a bit burnt out on these and don't give myself a break when I should. But the poundage progression is amazing over time, the forearm, biceps and brachialis growth is superb, and the pump ... holy cow. If someone can do one more "set" with remotely the same intensity, they have my respect.
Fat bar reverse curls are another goodie, especially if you do them in stages; e.g., sets of thirds, starting in the hardest to easiest ranges or the exact opposite (easiest part first, then midrange, then finishing off with full reps. Small breaks, like 10-15 seconds, are indicated between phases, though).