Ever since I first started playing I've been fascinated by running. I remember wanting armour for my very first character and desperately wanting to get that armour in the seemingly unreachable Droknars Forge. I remember being run down there the first time, by a dervish, I paid 2k for that run, but it was well worth it. Just 30 minutes later I was running around the snowy outpost buying my first 60 rating armour. I was suddenly invincible and cool-looking, that was worth so much more than 2k.
My running skills first started on my Necromancer. I'm not talking about Maive here either, I'm talking about Times Red Rose, the Necromancer that I first wandered the game with. Had I kept her, she would be around 3 now, if not 4. Still, I started running with her. By the time I had got her to the jungle she had mastered the run from LA to Ascalon with just speed boosts and a health recharge skill. I could run there in half an hour without anti knockdown or anti cripple skills.
These days all my running is done on my assassin (though in theory I can also run on my monk, necro, and basically any other character with "I am unstoppable" unlocked). My assassin, I find, is extremely easy to run on, and half the time I manage to do it on auto-pilot. Though I don't claim to be the best runner in the guild I can safely say that I am close second.
Most of my pride in my skill in running comes from mastering the runs in the southern shiverpeaks; and, in particular, the Beacon's Perch to Droknars Forge run, more commonly known as the Droks run. My build is to credit for this, of course, and my knowledge of the spawns, because that's all you need to do the run really, knowledge of the route.
When I'm stressed I also find the running therapeutic and will often run to droks or through Eye of the North just to let off steam. I remember one particular day when I ran a certain guildy's level 11 Necromancer through the entirety of Prophesies and Eye of the North just because I was stressed out. These are the times that I need to run, but most of the time when I do it I'm just enjoying myself.
I don't even charge.

