Net gun

Human incapacitating

 * http://www.taiwan-di.com Compressed air net gun
 * http://www.youtube.com/watch?NR=1&feature=endscreen&v=6rUNdpe2KHo

http://www.net-gun.com/ Uses air

http://lawenforcementmall.com/talon.php Uses air

http://www.instructables.com/id/Build-A-Net-Gun/ DIY

Other
http://www.instructables.com/id/GolfballAntennaNerf-Cannon---Build-One-That-Shoo/

http://www.instructables.com/id/Grappling-Hook-Launcher/

http://www.instructables.com/id/Titan-AS-V1-Super-Sniper-Mod/

http://www.chicompany.net/index.php?cPath=20_313_326&main_page=product_info&products_id=2187

http://www.instructables.com/id/Nerf-Gun-Mods/

http://www.instructables.com/id/Golf-Ball-Gun!!!-How-To-Make-One-That-Can-Shoot-40/

http://www.instructables.com/id/A-Coaxial-Golfball-Cannon/

http://www.spudgunextreme.com/

http://www.instructables.com/id/Micro-advanced-spudgun/

Vehicle incapacitating
Patent held by
 * http://www.youtube.com/watch?v=n8FNR8BryR0 X-net by QinetiQ corporation.
 * http://www.qinetiq.com/news/PressReleases/Pages/Next-generation-of-X-Net%C2%AE-family-successfully-complete.aspx

http://www.google.com/patents?id=r9XbAAAAEBAJ&pg=PA1&dq=qinetiq+spike+road+vehicle&hl=en&sa=X&ei=svlJT6jLMsLQ0QXi7ZiYDg&ved=0CDQQ6AEwAA#v=onepage&q=qinetiq%20spike%20road%20vehicle&f=false

http://www.google.com/patents?id=kwnKAAAAEBAJ&pg=PA10&dq=qinetiq+spike+road+vehicle&hl=en&sa=X&ei=svlJT6jLMsLQ0QXi7ZiYDg&ved=0CD0Q6AEwAw#v=onepage&q&f=false

http://www.google.com/patents?id=uWZWAQAAEBAJ&pg=PA1&dq=qinetiq+spike+road+vehicle&hl=en&sa=X&ei=svlJT6jLMsLQ0QXi7ZiYDg&ved=0CDoQ6AEwAg#v=onepage&q=qinetiq%20spike%20road%20vehicle&f=false

http://www.google.com/patents?id=OabwAAAAEBAJ&pg=PA9&dq=qinetiq+spike+road+vehicle&hl=en&sa=X&ei=svlJT6jLMsLQ0QXi7ZiYDg&ved=0CDcQ6AEwAQ#v=onepage&q&f=false

Links
PepperBall

Tazer gun