Christmas wouldn't be Christmas without the odd stocking filler or three, and the good old bicycle industry turns out loads of suitable inexpensive gizmos. Bike computers are always good fun - this Cateye Astrale comes in at under twenty quid and gives you a clock, elapsed time, auto start/stop, trip and total distance, current speed, average speed and of course the all-important maximum speed. That one's essential for the correct distribution of bragging rights... The Astrale also has a cadence function so you can see if you're actually pedalling like Lance or if you're slightly delusional.