DIY

• yagi in a can
  • o'reilly
• waveguide cantenna
  • tetra brick, with LOTS of VERY DETAILED information, info that's useful even on the other cantennas
  • instructions, with calculator. Just buy this kit and you're good to go.
  • another one
  • holy christ, that's what happens when someone goes nuts
  • even better: PVC lined with foil (easy to make it as long as you want, and no wrinkles inside) (HOWEVER, note that plastic waveguides are rare, possibly due to skin depth effects)
  • The Effect of Circular Directional Waveguide Antennas of Varying Volume on the Signal-to-Noise Ratio of a Wireless Network
• parabolic
  • biquad
    • more biquad: [1]
  • lots of REALLY GHETTO parabolic antennas
• slotted waveguide
  • seattlewireless
• pyramidal horn — $3, 32 miles, wow
• several
• thorough comparison
• homebrew shootout
• wifi-antenna.com, another overview