As in honour of my Christmas holiday I found two mathematics inspired items yesterday.
This ring is inspired by the Fibonacci sequence 1,1,2,3,... The pattern of the beads is the beginning of the sequence.
holmescraft's shop (via Neatorama)
This is a mathematically correct breakfast, a bagel cut and linked to make a Möbius strip
You can find the instructions here (also via Neatorama)