Display a block based on the term reference field of the current node What I'm trying trying to do sounds fairly simple, but I can't get my head around it.

I'm having 2 taxonomy vocabularies: machinery and batteries (both created with NAT for all that matters), and 2 content types which are named the same.

Both the content types provide the ability to check related items (a regular term reference field). For the machinery node the user can check which batteries are suitable, and for the battery node the user can check which machines use this battery.

Basicly what I'm trying to is: if you're on a page about a specific machine, it should show the batteries that are related to it, be it as teasers (or fields) in a block. And vice versa: when you're on a page about a specific battery, it would show all the machines in which it fits.

I've been boggling around with relationships and contextual filters, but it just wouldn't work out so far (spent a couple of hours here). Does anyone have an idea how to sort this out please?
There's possibly an easier way with the References module. In that case it wouldn't even require NAT, but just a View with contextual filter based on the Reference field.