A dynamic DNS script (written in PHP) that uses CloudFlare's free DNS and their API to set up a dynamic DNS record pointing to your server.
git clone https://github.com/lyoshenka/cloudflare-ddns.git
cd cloudflare-ddns
cp config.php.skel config.php
### Edit config.php - enter your CloudFlare credentials and domain details
./ddns.php
If everything works, put it in your crontab.
0 * * * * /path/to/cloudflare-ddns/ddns.php -s
Uncopyrighted. Do whatever you want. I hope this code makes you rich. Spiritually.
For an even simpler version written in Bash, see this gist.