Create and use a swap file

Instead of letting space go to waste in a swap partition, Linux can use a small swap file instead: 

   1 sudo dd if=/dev/zero of=/swap-file bs=1M count=255
   2 sudo mkswap /swap-file
   3 sudo swapon /swap-file

To automatically bring it up on reboot, place into fstab: 

/swap-file none swap sw 0 0

(!) Note: The Linux kernel does not support sparse files as swap files. It's also best to create the swap file immediately after filesystem creation to insure a contigiuous file. Other than that, choice of filesystem does not matter. Reference on LKML.