$64.99 EnerGel RTX Gel Pen, Retractable, Fine 0.5 mm Needle Tip, Blue Ink, Silver/Blue Barrel - Zerbee
From 1 to Pen Reviews: A Student's Guide to Gel Ink and Ballpoint Pens: Review: Uni-ball 
Only decent 0.5mm pen I could find. Why is majority of pens 0.7mm? : pens
