>>2936
Although for me it's incidental, and not chronic, these are some things that help me:
Do not eat within hours before going to bed.
Sleeping on your right side with your legs curled (famous folklore, but it works for me).
Alternatively, laying stiff upwards with your arms across your head.
Do brief exercises (keep it simple; pushups or warm-up) - this will completely wake you up, but it usually helps.
These also work if a developing hang-over is keeping you up!