I've been trying that for a few years, even with some success. Only to decide it wasn't worth the hassle.

Install a server? Just leave out KDE, KDEI, T, XAP and XFCE. X has a few (six or so) dependencies needed by some things in N like PHP, but it doesn't hurt anyone to install the whole load and stay in init 3. On the other hand, what I do on a server is only start with SSH and syslog services, and going on from there, only activate needed services as I configure them.

Yep, I just did this when I set up a Slackware server on a VPS the other day. I think I also unchecked the FAQ and games.

This may be of some help to those interested in this thread:

a/aaa_base-$SUITE-$arch-?.txz
a/aaa_elflibs-$SUITE-$arch-?.txz
a/aaa_terminfo-5.8-$arch-?.txz
a/lilo-2?.?-$arch-?.txz
a/bash-4.?.???-$arch-1.txz
a/bin-11.1-$arch-1.txz
a/bzip2-1.0.6-$arch-1.txz
a/coreutils-8.19-$arch-1.txz
a/dialog-1.1_20100428-$arch-2.txz
ap/diffutils-3.2-$arch-1.txz
a/e2fsprogs-1.42.6-$arch-1.txz
a/elvis-2.2_0-$arch-2.txz
a/etc-14.0-$arch-1.txz
a/findutils-4.4.2-$arch-1.txz
a/gawk-3.1.8-$arch-1.txz
a/glibc-solibs-2.15-$arch-?.txz
a/grep-2.14-$arch-1.txz
a/gzip-1.5-$arch-1.t?z
n/iputils-s20101006-$arch-?.txz
a/logrotate-3.8.2-$arch-?.txz
n/net-tools-1.60.20120726git-$arch-?.txz
n/network-scripts-14.00-noarch-?.txz
n/openssh-6.1p1-$arch-?.txz
a/openssl-solibs-1.0.1c-$arch-?.txz
a/pkgtools-$SUITE-noarch-?.tgz
a/procps-3.2.8-$arch-?.txz
a/sed-4.2.1-$arch-?.txz
a/shadow-4.1.4.3-$arch-?.txz
a/sharutils-4.11-$arch-?.txz
a/sysklogd-1.5-$arch-?.txz
a/sysvinit-2.88dsf-$arch-?.txz
a/sysvinit-functions-8.53-$arch-?.txz
a/sysvinit-scripts-2.0-noarch-??.txz
a/tar-1.26-$arch-?.tgz
a/udev-1??-$arch-?.txz
a/util-linux-2.21.2-$arch-?.txz
n/wget-1.14-$arch-?.txz
a/which-2.20-$arch-?.txz
a/xz-5.0.4-$arch-?.tgz

The above will work for at least the Slackware 14 32 or 64 bit x86. You might have to play with version numbers for older releases or current if you are trying to get the shell to match. This is more or less the minimum set of packages that you need installed for Slackware to boot and the package tools to work. Its a good starting template for virtual servers and containers (you can drop lilo in the latter case). Ponce deserves credit for about 80% of this list I borrowed it some years ago from one of his scripts.

If you really want a minimal purpose built system with only the binaries you need to support a specific application like a LAMP site it may be easier to build up from here adding what you do need a package at a time than to try and figure out what all you don't.

I've been away for some time, but now i'm planning to do some test in VM. I'll post the results.

I wrote that to build lxc containers, but I borrowed the list too from vbatts (thanks again!) at the time ;)

Now I'm doing them in a easier way with a slackpkg template, where I don't have to specify the versions