glc is a program which can allow users to capture videos of games utilizing OpenGL acceleration. You can see some examples of it in use from Linux Game Cast:
http://linuxgamecast.com/

After some trial and error, I managed to get it installed and working properly on a system running Fedora 16 by using the following commands. This assumes that you have RPM Fusion installed, if not you can enable it from here:
http://rpmfusion.org/Configuration

Remember: You must replace all instances of the word "user" with your account name.

[user@computer ~]$ su -
[root@computer ~]# echo 'user ALL=(ALL) ALL' >> /etc/sudoers
[root@computer ~]# yum install automake glibc-devel gcc git-all gcc-c++ mencoder lame ffmpeg
[root@computer ~]# yum groupinstall "Development Libraries" "X Software Development"
[root@computer ~]# su - user
[user@computer ~]$ cd Downloads
[user@computer Downloads]$ mkdir glc
[user@computer Downloads]$ cd glc
[user@computer glc]$ wget https://github.com/nullkey/glc/raw/master/scripts/glc-build.sh
[user@computer glc]$ ./glc-build.sh
[user@computer build]$ su -
[root@computer ~]# cd /home/user/Downloads/glc/glc/build
[root@computer build]# make
[root@computer ~]# make install

When it comes to actually using glc to capture videos, I will refer you to this exellent article on the subject:
http://www.dedoimedo.com/computers/glc.html

There is also plenty of documentation available from the glc website:
https://github.com/nullkey/glc/wiki