This is how I got the Microtek Scanmaker X6 Parallel port scanner to work with Linux. If any of you are looking for a good scanner, this one is only around $100 and one of the few new scanners that you can just walk into a store and buy, that works with Linux.

First, use the 2.2.14 (or whatever current version is support by the patches below) kernel. I won't go into how to install and compile the kernel sources here, but there's a good NHF on that subject. Once you have the sources in /usr/src, get the ppSCSI patch from:
http://www.torque.net/parport/ppscsi.html. OR http://people.redhat.com/twaugh/parport

Once you download the patch, move it to /usr/src by typing:
(Make sure you are root)
mv ppSCSI*.patch /usr/src

Then type:
patch -p0 < ppSCSI*.patch

It should patch without any problems. This will not work with any kernel other than 2.2.10, at least the ones I have tried.

Now that the kernel is patched, configure and compile the kernel. Under SCSI support, you must say either yes or module to SCSI support and Generic SCSI support. Under SCSI low level drivers, you must choose module for parallel port SCSI adapter and Onspec 90c26 adapter. If you try and compile them into the kernel, it will not work....for some reason they must be built as modules. Now finish your configuration and compile the kernel, then make and install the modules.(make modules, make modules_install) Fix your lilo and reboot. (If you haven't recompiled a kernel before, check the NHFs and HOWTOs for better instructions)

Now you have to get the SANE scanner drivers. Go to http://www.mostang.com/sane and download the latest version.

It is important that you download the source instead of an RPM because some changes have to be made. Once you download SANE, go to ftp://ftp.muc.de/people/bernds/mtek2 and download the newest version of the microtek2 backend. The version that comes with SANE scans very green and the new one takes care of this problem.
(This might be fixed with the current version, so you might want to just try the RPM anyway and if you are happy just skip the following steps to build SANE)

Right now the newest stable release is microtek2-0.8.tar.gz. Once you have it downloaded, extract the SANE sources like this:

tar -xvzf sane-1.0.1.tar.gz

and then extract the microtek backend:
tar -xvzf microtek2-0.8.tar.gz

When you extract the contents of the backend, you will have 2 new files, microtek2.c, and microtek2.h. Copy these two files into the backend directory of the SANE sources. It will tell you that the files already exist, but just overwrite them. Now cd into the sane sources and build them.

cd sane-1.0.1
./configure
make
make install (you must be root)

Now you're almost done!

Now, before you reboot, make sure your scanner is on. The Parallel 2 Scsi code won't find it if you turn it on after you boot up, it will say no Sane device exists. After you reboot, you have to load the modules you built.

If you have a recent system (such as Mandrake 7.0), then installing a module is fairly easy. In fact, you can just install the most important module and it will load any other dependant modules automagically. Try just:

(as root) insmod onscsi

If that works, you are all set.
Otherwise:

As root type:
(if you compiled SCSI support as a module, you will have to load it first with insmod scsi_mod)

insmod ppscsi
insmod onscsi

Either way:

Mandrake 7 (and others): add the line(s) into /etc/rc.d/rc.local at the end.

Slackware: It is easiest to just add these modules to /etc/rc.d/rc.modules so they are loaded each time you boot up. other distributions.

Next:
As root, cd into the tools directory of your sane source directory. There is a small program there called find-scanner.

Type ./find-scanner -v, and it will find your scanner and tell you where it is. You may have to scroll up a little to find it. It's usually /dev/sg0, or /dev/sga.
(It might show as BOTH in which case)

You can also do (as root)
ln -s /dev/sg0(orwhatever) /dev/scanner
That way it's clear it's a scanner device.

When you know which one it is, as root do:
chmod 666 /dev/sga(or whatever it is)

This makes it so anyone can use the scanner.

Now type scanimage or xscanimage and enjoy!

Also, Xsane is similar to xscanimage, but nicer, and also works as plugin for Gimp. Just make a link from Xsane into your Gimp plugin directory.

This scanner won't do image previews under Gimp (it does otherwise), but it works great. It also works using StarOffice REALLY well. Just select Acquire Image and it brings up your scanning tools.