Hey Sergey!

 SS> There is a laptop, ancient. It only has 128MB of RAM (and a 40GB
 SS> IDE drive!). What Linux can I install on it?

Have a look at some of the older slackwares at ftp://mirror.csclub.uwaterloo.ca/slackware/slackware-iso/ as they have versions nobody else has, not even slackware.  Offhand I'd guess something like slackware-10.0 or thereabouts should work.

 SS> I want to deploy FTN software on it, and a website (with a load
 SS> of about zero). Is it even possible?

Yes.  How much do you know about installing linux distributions?  Also does the laptop have a bootable CD-ROM?  That will make a HUGE difference.

Life is good,
Maurice

... Ne m‘g werig mod wyrde wi¨stondan, ne se hreo hyge helpe gefremman.
    A weary mind cannot withstand fate, nor a sad heart offer help.
--- GNU bash, version 5.1.8(1)-release (x86_64-moosile-linux-gnu)