The difference is about 0.5%. A mass weighing 100kg at the north pole would only weigh 99.5kg at the equator. Most of the difference is the centerfugal force of the earth’s rotation.
I’ve not checked the numbers, but apparently it’s detectable in Olympic sports. More height records get broken at equatorial latitudes that higher ones.
I had good luck with these at my wedding. Instead of disposable cameras, I put cheap digital cameras. It didn’t take long for guests to realise that the pictures were appearing on a large tv, in a sideshow. People got a lot more creative when they realised they would be seen quickly, not weeks later.
I managed to get them working without proprietary software, too. The onboard script logged into WiFi and uploaded the photos over ftp.
Given their size and the level of tech at the time, it was pretty impressive.