Questions about software on Internet

[rgg@telerama.lm.com]

On comp.sys.binaries.apple2 and in various ftp sites I have seen software 
that I would like to download and use. However, I'm worried about problems 
with the software. For example, I remember back when the GS first came 
out there were a few programs which could accidentally wipe out entire 
hard drive volumes. Is it likely that any programs available on the net 
will do this or something equally nasty? Also, have there been any 
occurances of viruses in apple software on the net? 

Thanks in advance,
 
Rich