I have read in relation to being creative that the things we do as play should actually be what we do in our work all the time. The restrictions of 'I have to get this done' more often than not stifles our creative side and keeps us in the safe zone. After all being safe is something we are at ease with.
So part of my play as I have posted before is computer generated graphics using various softwares.
One of my favourites past times is playing with fractals, the outcome due to inputting various numbers often results in an outcome not intended, and therefore is totally free from self imposed restrictions. Over time I have been able to gain enough knowledge to have some control over the outcome but not full, hopefully I never will as the excitement of coming up with something totally unique is the most enjoyable part.