Old Pc's newer user, looking for new tricks

[mulege]

Ok so I have a VERY old PC in fact it's a 1986 IBM model M with MS dos and win 3.11.

I got bored with windows fairly quickly so I spent some time messing around in dos as well as learning some of the deeper workings of it, and I have again become bored... I have done a lot of things but some Historical Computer things interested me, such as how were computer viruses propagated way back when ect...

Due to me collecting technology I can simulate the BBS systems here at home with a couple old computers running dos here to work with I was wondering if you guys had any Ideas?

oh btw I do have my (BIG) dos manual here so no worries about getting stuck