Make 2.4GHz parabolic mesh dishes from cheap but sturdy Chinese cookware scoops

You also need a USB WiFi adaptor ! The largest (300mm diam)shows 15-18dB gain (enough for a LOS range extension to 3-5km), costs $5 and comes with a user friendly bamboo handle that suits WLAN fieldwork- if you can handle the curious stares!

THOUGHT - fit this thumb at the focal point of a directive antenna? Quick trials with NS 0.4 showed useful gain with even a bare metal plate behind it. Perhaps the classic "Sardine can" biquad reflector? Simple metallic plates behind the unit gave significant weak signal boost, espec. when spacings were ~32mm ( which of course is 1/4 wavelength at 2.4GHz). With DIY dishes (each 15-20dB ?) then range increases to say 5-10km may result - dB maths says each 6dB gain will double the range.