Don't Reboot After Adding Partitions - partprobe!

Another one of those topics where about 50% of the class bustled in excitement over learning something new and simple came up today.  After running fdisk, you will almost always get an error about the kernel not using the new partition table you just modified.  Before GNU released parted, you had to reboot in order for the kernel to purge it's cache and reload the partition table, but now, all you need to do is run partprobe after exiting fdisk.  AFAIK, partprobe is included in most all distros.