All, thanks for all the info! I've got less on my n900 now.

To summarise:

I got it via aspidites suggestion by adding the TOOLS repository "http://repository.maemo.org fremantle/tools free" to
the apt sources, and then running "apt-get less".

I'm not familiar with apt (am more a fedora guy...) but I noticed all repositories can be browsed via <url>/pool
(e.g. the http://repository.maemo.org/extras repo can be browsed via http://repository.maemo.org/extras/pool),
but this does not work for TOOLS repo.

Adding the SDK repository http://repository.maemo.org/pool/fremantle/free/ as suggested by Matan did not work.
I can browse this repository on the web, but adding it to the repositories (using application manager or using
aspidites way) did not work. I get the following error:

Failed to fetch http://repository.maemo.org/dists/fr...armel/Packages

So I could not run "apt-get less" from SDK repo.

Als also wanted to add the 'bc' package. I can see it in the SDK repository, but it is not in the
TOOLS repo...