playing safely...

[235u at comcast.net (D.E. Chadbourne)]

hi, i have set up a small network with a mac, some windows and one linux
box and desire to play with various nefarious pieces of code to see how
they work better.  any ideas on how to safely download, store and
control such a collection?  this is just for fun and not for business. 
thanks for any suggestions.  -eric.