I would take along a copy of pari and maxima.

In this situation it would be nice to work on something that is relatively stable, so you don't miss updates. It should also be challenging, to take advantage of your time availability. Most important it must be interesting to you!

If it is interesting enough to you, please spend some time writing about what you learn, and let us know how it turns out. I would especially enjoy reading about learning Festival.

It should work perfectly the first time! - toma