Powell's Technical Books used to be my favorite place to hang out. I would ride downtown in the morning and spend an entire day there, scanning every shelf in my fields of interest, reveling in periodic hits of serendipity. Since PTB closed, I've been back once. It wasn't worth it any more. I'll admit that I did like it better back before the store was spruced up to be like a Borders.
How is it like Borders? It's a warren of different rooms on different floors, half of which are more like a warehouse than a retail store, with a huge selection of used and new books shelved together.
I loved the separate technical books stores, too, although they still have a great tech section in the main location. I assume the standalone PTBs shrank then closed because people were browsing more than buying.
I'm still mourning the loss of PTB. Not just a bookstore, more a collection of hundreds of subjects in excruciating detail, rabbit holes that would take years to follow of programming, electronics, physics, machinining, steam power. I hate to think what happened to it all. It really did feel like a reservoir of discarded knowledge, like a massive grimoire of nerding.
The technical sections on the top floor by the rare books area is still pretty good, but it has none of the "science gizmos" and the feeling is just that of a regular section.
