Guess it's a bit older, but I found this game via in4mador.com and enjoying played it from start to finish (needed two tries).
http://www.teravisiongames.com/fly/indexAds.html
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http://jayisgames.com/archives/2008/02/lt_fly_vs_the_spiders_from_above.php
Lt. Fly vs the Spiders from Above is a combination puzzle/shooter game that will leave your head buzzing. On the left side of the screen (company, left face!) is a block puzzle with a light twist. At the top left of the board is a fly holding a block of one color. Clicking anywhere within the grid will replace that block with the color designated. If you create a cluster of four or more similarly-colored blocks, they will disappear, leaving the rest of the blocks to topple down into place, and possibly cause some delightful combo action. Also in the grid are special blocks with bullets, flamethrowers, and bombs. If you work these blocks to the bottom of the screen, they get added to your arsenal of ammunition.
That ammunition gets used on the other side of the screen (company, right face!). Using the fly-operated cannon at the bottom-center of the screen, simply aim and fire at the spiders descending from the sky! You'll have to be careful, since your cursor will disappear once you cross into the right side of the screen. Keep an eye on the angle of the cannon's elevation (or just get used to blindly mousing around), or else you'll waste precious bullets. If you defeat enough spiders, you'll move on to the next invasion, where more of the creepy-crawlies await!
http://www.teravisiongames.com/fly/indexAds.html
