Need something to do in my spare time, what simple DIY/Woodwork/Computer projects can you suggest?

I work friday and saturdays and am at the gym monday, wednesday and friday in the day. For those days off i am so bored I dont like my job its too boring so overtime is a last resort [i work in a supermarket on the checkouts]. I am really into DIY/Woodworking and also computers. Can anyone suggest and simple, enjoyable projects I can do that involve any of those interests?