My high score was 34,340!
Quick strategy guide from the programmer:
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Your melee attack makes you invincible while in the air. It's also great for picking off enemies in a long chain, ideally only alerting your subsequent target. With each melee your rate-of-fire and 'ammo' for the ranged psionic attack grows. Your ranged attack does deals damage in an area so its a good idea to build up its power for the hordes later on.
(SPOILERS\)