So I don't know how it slipped my notice, but RPGNow and DriveThruRPG have added two new B/X D&D products to their site. Both are tough acquisitions on eBay, fetching quite a price for those trying to find physical copies.
Champions of Mystara: Heroes of the Princess Ark is a boxed set that details the adventures of the crew of the airship known as the Princess Ark, which was the subject of an ongoing series featured in Dragon Magazine back in the day. It's seriously cool stuff, and given that if you're lucky enough to find a used copy for sale you're likely to pay $100, it's damn near theft at $9.99.
Also, we've now got DDA3: Eye of Traldar available, which is your traditional "track down the MacGuffin" adventure and in spite of the high prices physical copies fetch, it's never been anything exceptional in my opinion. That being said, it's perfectly serviceable for a night of adventure and $4.99 is just inside the reasonable price range.
Apparently, in my blindness, I also missed the fact that OBS has added the Hollow World Campaign Box
For all the complaining I heard back in the day that B/X and Rules Cyclopedia D&D were "vanilla," I think supplements like Princess Ark and Hollow World certainly prove that to not be the case. These were fast, fun, gonzo adventuring from my care-free days of rolling dice and saving the world.