I want to remote control Google Doc Presentations. Is there an app for this?
Bonus point if it can connect via Bluetooth to my Linux-based PC.
You could simply use a bluetooth/wifi mouse app like PRemoteDroid. There are a bunch of others, and generally speaking they just allow your device to be used as a mouse/keyboard input. If you can pair with your PC it should work, although I've never tried it myself (I do use PRemoteDroid to pair with and remotely control my Xoom, though; works great).
Another option would be some kind of VNC or remote desktop client, but that's not as lightweight and some of them don't support Linux (Splashtop, for example, doesn't have a Linux server, IIRC).
Google Presentation Remote is great and really easy to use on your Android phone. It is dependent on the Chrome Extension "Google Presentation Remote".
I'm the developer of an app called WatchPresenter, which lets you control Google Slides from your phone. It doesn't require phone and computer to be on the same network (as long as both have Internet it will work).
You control the slides by using the volume buttons, so you can switch the phone's screen off (easier to handle without hving to look at the phone, and less risk of unintentional clicks).
Additionally, if you have a Android Wear device, it lets you control the presentation with wrist gestures.
I did end up using the paid app Presenter. I liked the interface and the way it dominantly shows the presentation time.