extract multiple rar

Example:
filename.rar.001
filename.rar.002
filename.rar.003
filename.rar.004
filename.rar.005

//command
cat filename.rar* > filename.rar

rip dvd and mount iso dvd in ubuntu

to rip
dd if=/dev/sr0 of=thecorrs.iso bs=1024
to mount :
sudo mount -o loop -t iso9660 /wherever/iso/image/is/image.iso /media/iso/
to umount :
sudo umount /media/iso

*force umount
umount -f -l /mnt/cdrom

No sound in Ubuntu 9.04 firefox,vlc

sudo apt-get remove libpulsecore9 pulseaudio pulseaudio-esound-compat pulseaudio-module-hal pulseaudio-module-x11

*No sound after upgrade when using meebo to send a message in the first time, meebo need sound to beep and then the audio is muted