Recently I needed to use Canon Lide 100 scanner. When I plugged it into my Fedora laptop I realized that this scanner is not supported by Linux (sane or simple-scan). A bit of googling took me here. Looks like support for Canon Lide 100 is already in the git repos of sane (sane-backends package, specifically), but you have to do a bit of circus until your favourite distro starts shipping more recent version of sane.
I followed the instructions from there, but slightly customized it for my Fedora 13:
# yum install libusb-devel
# git clone git://git.debian.org/sane/sane-backends.git
# cd sane-backends/
# ./configure --prefix=/usr --sysconfdir=/etc --localstatedir=/var
# make
# make install
Now edit /lib/udev/rules.d/65-libsane.rules to add these lines about the scanner:
# Canon CanoScan Lide 100
ATTRS{idVendor}=="04a9", ATTRS{idProduct}=="1904", ENV{libsane_matched}="yes"
# reboot
At this stage the scanner should have worked, but it did not :-( I took another look at the sources of sane-backend. It looked like the file backend/genesys/conf should have been copied to /etc/sane.d/genesys.conf, was somehow wasn't. I manually copied this file over:
# cp ./backend/genesys.conf /etc/sane.d/genesys.conf
Voila, Canon Lide 100 now works with my Fedora 13 using xsane.