Some of the interesting parts of botnets have commercial or research value.<p>As an example... I find it very difficult, in general, to install software onto multiple Windows machines.  Different versions of DLLs, differing Windows features, differing filesystem layout, etc.  The botnet control system seems to reliably install on all sorts of machines, without needing 3 restarts and without asking lots of dumb questsions.<p>Making installing real programs this easy and reliable would be quite nice.