Cool new product you may find useful

[Dannyalcatraz]

I just made some out of old hex or graph paper and laminated them.

 

[jgsugden]

I found that it was better to make my own using actual circles or quarter circles, so that the PCs are not limited to firing their spells on the grid lines. It is a lot nicer if the PCs can aim that cone of cold at a 30 or 60 degree angle instead of only at 0, 45 and 90 degree angles.

 

[Monte At Home]

I love these things. We used them in my game just last night, to determine if the entire area of the cube of force (and the four PCs inside) was within the area of the dimensional rift of a chaositech void grenade (that had just detonated inside the horrifically powerful blasphemous mimic) or just within the larger area of its gravitic pull.

Man, I love D&D.