I was just sitting here thinking that it would be helpful to have a thread to address parts cross references to help in a pinch. Here are a couple I've picked up off of here. I thought it would be nice to have a one-stop-shop:

Oil filter - 07+ Toyota Yaris 1.4L
Fuel pump (not assembly) - 03 Ford Mustang 3.8L - Walbro 521
Oxygen sensor - 87 Chevy 1/2 ton 4.3L - Bosch 12014
IAT - 97 Ford F-150 4.6L

If I'm wrong, please correct me. As Harley stops supplying these parts, it would help to know how to keep our bikes running.