I don't know if I should say: run, ruh-uhn, roo-uhn, or ??
Otherwise, it's nice and short.
Some domainers swoon for 4L names.
You could sell it to them.
Ruun dot com was regged continuously from 2003 until this year; it deleted and was created two days ago, so technically it's now only aged 2 days even though it has a 10 year history; it's a pretty good LLLL which means the prev owner let it drop and the new owner used a dropcatcher to pick it up. For some reason the new registrar 1hostjapan dot com is not showing any owner details at the moment. Nameservers are interim which means things are still in transition, I expect 1hostjapan is a dropcatch registrar being used by one of the big dropcatchers. You'll have to wait to see updated whois records to find out who ends up with this domain.
Also you'll want to ask this thread to be moved to the 'pre purchase appraisals' section, this section you're in now is only for domains you currently own.
But I think it would sell for reseller range of low to mid xxx, maybe higher because people are still half-rabid about decent LLLL, and end user interested in branding might pay low x,xxx and up.