Switch to IPv6: Shift+6
Switch to IPv4: Shift+4

Search: CTRL+F or key Shift+S
Toggle hints: Shift+H
Toggle AS information: Shift+I
Toggle AS listing: Shift+L
Toggle neighbor highlighting: Shift+C
Toggle link visibility: Shift+V
Toggle debug output: Shift+D
Toggle rendering in background: Shift+E
Toggle text labels: Shift+U

Zoom/Pan: Mouse scroll/drag
Continous movement: Shift+A
Shape nodes into a circle: Shift+B
  (Use Shift+B to expand/contract circle)
Default shape: Shift+N
Lock node position:
  While dragging, Shift+release mouse
Release all node locks: Shift+G
Center node: CTRL+Right Mouse
Center viewport: Shift+W

(In/de)crease charge : Home/End
(In/de)crease gravity: Ins/Del
(In/de)crease link distance: PgUp/PgDown
(In/de)crease friction: Shift+(PgUp/PgDown)