Not too long ago I came across a feature within Cubase that I didn't actually know existed- the MIDI send. The reason here is two-fold. First, I didn't have a need for it previously, and second, it's hidden by default!
The purpose of the MIDI send is to allow you to send the MIDI data of a MIDI track to more sources than the instrument it's directly connected to. This type of thing could, for example, allow you to easily layer synths using a single MIDI track, making sure everything is always in sync. In my case, I was looking for a way to easily use a sampled kick drum along-side of EZDrummer.
One could argue that this is a trivial task. You simply create two MIDI tracks, one for the kick and one for the rest of the kit. The problem is, now you have to edit the kick drum separately from the rest of the kit. It's much easier, in my opinion, to edit in a single piano roll.
For those who are in the dark (like I was) regarding the whereabouts of the MIDI sends, never fear, they are easy to find. You simply right-click in a blank area of the channel inspector column (far left side of screen by default) and check that you'd like to see MIDI sends. As a note, you should probably do this while inspecting a MIDI track.
Here is a partial screen shot showing a potential setup. You can see the MIDI track for Groove Agent SE doesn't have any MIDI data, as it's all coming from the track labeled "Metal Machine." As a note, in my situation I was looking to replace the kick, so the EZ Drummer kick is muted (not shown).