Nick Jensen has a lot of free time and a big love for Halo: Reach. Combine the two and you get an all-LEGO Halo sniper rifle, potentially the deadliest LEGO object ever built (with the exception of the Death Star… maybe). Formally known as the Sniper Rifle System 99 Anti-Matériel, this awesome build comprises an unknown number of bricks, but is measured at 63 inches long and weighs approximately ten and a half pounds. This is about on-scale with the gun in-game, which is cited as being 5.5 feet long. The SR99 features a removable magazine, sliding bolt and moving safety, and took roughly four months to assemble. Not bad.
Jensen has a few other LEGO Halo weapons, too, and there’s a nice post about his build process for the SR99 at The Brothers Brick.