While he was in The Land Down Under, RS recommended the manga trilogy "Maniac Road" by Shinsuke Kurihashi. Trusting in his otaku knowledge, I immediately ordered it from Amazon US. Ripped through the lot in two hours - what a beaut yarn!
Homeless fanboy Takezou helps sweet Haruna, violent Aoba and cute Isuzu save their tiny shop in Tokyo's Akihabara district from bankruptcy, then sets about transforming it into a Mecca for hard-core collectors. He's frequently forced to demonstrate his skills by a guy called Mikasa, the owner of a gigantic rival operation who's keen on Haruna.
This gives the author the perfect excuse to dig deep into hobbies such as military model making (his personal passion), cosplay, paintball, ultra-realistic dolls, tabletop role-playing and crane games (aka UFO catchers).
At this point, you've already made up your mind whether you wanna travel the "Maniac Road", so I'll cease typing.