Hold down the hotkey and left-click to drop in the node. The hotkeys are as follows:
A -Add
B -BumpOffset
C -Comment
D-Divide
E-Power
F-MaterialFunctionCall
I-If
L-LinearInterpolate
M-Multiply
N-Normalize
O-OneMinus
P-Panner
R-ReflectionVector
S-ScalarParameter
T-TextureSample
U-TexCoord
V-VectorParameter
1-Constant
2-Constant2Vector
3-Constant3Vector
4-Constant4Vector
Shift + C-ComponentMask
