Twelve years ago, give or take, I needed to string some letters together to label my very first RP character on the Star Wars Galaxies Roleplaying Forums. Sure, it was Star Wars, so vowels weren't strictly necessary, but I settled on Dirin as something that would be easy to read.
When I later started using the tag in a variety of MMO games, I discovered that its pronunciation was open to some interpretation (I think DEE-rin, but have heard Durin, Durn, dur-RIN). I also discovered that this particular combination of letters has about a 50% chance of already being taken in a sample of everything I've ever needed a tag for.
The resulting naming convention was to use a-consonant-that-works + "irin". On protag, I started with the now-traditional "Dirin" and it happened to be available.
As for Dirin the character, I don't expect he's even a blip on the radar in the truly vast universe of Star Wars fanfic, but his story arc included two 200-page posts and served as my introduction to Online Collaborative Storytelling (<- a name that I've found to work better than 'Star Wars Fanfic' in certain circumstances (i.e. giving an academic presentation, describing my hobby to a police officer, talking to girls.))