In order to make your glow sticks super bright, just crack them, put them in a microwave for 10 seconds. WARNING: Glow sticks can pop in the microwave if left in to long.
I bought these glow sticks, 1000 for $40 on e-bay, some worked great, but others were kinda dim, a search of solutions turned up this. The life of the glow stick is shortened slightly (12 hours instead of 24) but is much brighter and more useful.
Step 1: NUKE!
Just take dimming glow sticks and place them in the microwave for 10 seconds...
Microwaves excite the hydrogen peroxide in the glow sticks and make the glow sticks react faster (brighter). They will still last for hours though when they start to die, they die for good.
DON"T DO IT FOR MORE THAN 10 Seconds.