There is a nice twist with these clock kits, you can replace the hour hand with a disc or square with the hours written on, and then make a fixed hour hand pointing up from the bottom. The square rotates and the hour hand will point out the hour on the disc, and then the minutes can be written around the outside as 5, 10, 15, 20 etc instead of the usual hours.
I have one on the mantelpiece and I enjoy watching people get confused trying to work it out, however it is quite simple and easy to read when you get your head round it.
Another design I saw (which is a bit more complicated to make – though probably possible with a spoke and some patience) is to have a long hour hand that goes in a big spiral, the hours are written down the centre of the clock face in a line, and where the spiral crosses the hour indicates the time.