pound sand

Short definition from Wiktionary

Verb

1. 1
   To engage in a simple useful activity, which anyone would know how to perform, other than those who are incapable of any simple activity.
2. 2
   To engage in a futile activity.
3. 3
   To go away; get lost; go to hell; To waste one's own time (with some other meaningless task) rather than waste the speaker's time with something equally irritating or pointless.