Not sure if it counts as beyond playing around, but I used Wolfram Alpha quite a bit through school & university for checking my answers or how to do something I didn't have an answer for (it shows steps to get to solution, not just the solution) or to play around with parameters to get a better understanding of something - 'what if..' - pretty useful. More useful and easier to use than the TI Nspire CX CAS (I think) that I had, briefly, for that reason.