A cheap, cool, teenage way to cover all the stuff on your shelf wall is to camouflage it with shower curtains.
Step 1: Prep the Hang Distances.
Just hang electrical conduit from perforated strap leaving a space at the top and bottom for air flow.
Step 2: Shape to Suit.
Use angled junctions to go around corners and make the shape of the wall to suit your basement. Hang cheap shower curtains and you are disguised.
Step 3: Finished !
Voila' All your stuff is obscured from eyes and yet readily accessible. No cluttered storage rooms.