Reminds me of classic Mac games, both graphically and mechanically. Title, instructions, and credits on the left, game on the right. Feels fairly nice, functions properly, and pretty fun! Sound effects are decent, and the lack of music is a-okay in my book.
Difficulty wouldn't be too bad if there were checkpoints every 5 or 10 levels, but as it stands now, death is way too frustrating. Movement's a little slippery - I think I'd prefer if the player character stopped abruptly instead of sliding to a stop. I also kind of wish I could turn the laser OFF sometimes, for strategic maneuvers, but I understand if that's supposed to be part of the challenge. I'm also not so fond of the controls, which I think other folks have mentioned. WASD+mouse is fine, but shift and space to change lasers is a bit awkward - I'd say Q & E to change might feel nicer.
There's also a bug where, when you die, the level counter doesn't reset, so I beat the game on level 90 or so, haha. Obviously extremely minor, but figured I'd point it out.