How to buy items in The Binding of Isaac

The music files are located in whatever drive you installed Steam on, then this path:

\Steam\steamapps\common\the binding of isaac\The Binding of Isaac Soundtrack

Your files should be there and ready to play! Alternatively, you can go to the steam client and look under library > music, and see all the purchased soundtracks you own.

If you're on a Mac you'll find that path in [Home]/Library/Application Support/Steam.

You can get the following pickups to cross gaps:

• Ladder - Cross 1 gap spaces
• Lord of the Pit - Gives you the permanent ability to fly
• Hanged Man Tarot Card - Gives you the ability to fly for your current room only, one time use
• Transcendence - Like Hanged Man, only a permanent upgrade
• The Bible - Gives you flight when used for your current room only
• A Pony - Usable item that also gives you constant flight (added on Halloween update)
• The Pinking Shears - Usable item that separates Isaac's head and body, allowing you control of the head (essentially another version of the Bible as a usable item, with added benefit of a free "Super Meat Boy" for that room while your body attacks enemies)

Credit to Chris Rasys for mentioning the Magnet, which can pull items towards you from a short distance away. While not technically the same as crossing the gap, it serves the same effect for the purpose of retrieving unobtainable items.

In this case, where there's a rock right next to the gap, using a bomb will plug the hole. This appears to be fickle though, as I've had bombs just destroy the block and not plug the hole. It appears that you have to be pretty precise in terms of the bomb placement so that the blast is exactly horizontal/vertical to the block.