I've been using Cordless RumblePad 2 as a controller to manipulate my Mac mini from the couch by using GamePad Companion. It worked okay but the application apparently is not maintained anymore and there are some actions that I'd love to map but couldn't.
So anytime I need more actions like changing the system volume I either have to use Apple Remote or ThinkPad X40 over synergy. it sucks. I was about to buy the bluetooth clickpad Dinovo Mini but it's pricy ($150) and I have been waiting for its price to go down, which doesn't seem to happen.
But fortunately I just found a better app to solve all of these problems: ControllerMate. It basically allows you to program blocks of events and actions based on any HID device inputs. Its modifier functionality to map multiple actions to one key is a killer.
Its GUI is so developers oriented and might not be easy to figure out if you're not programmer type. But once you go through the tutorial, it's brilliantly easy and it took just half an hour for me to map all of functionalities I wanted.
Now I can use the left analog stick to move the cursor (which can be accelerated when pushed with L1), right analog stick as a scroll wheel, right buttons as a left/right click, R1/R2 as Expose/Dashboard, and then use the arrow keys as arrow keys and also a replacement of Apple Remote when pushed with L1 button (using RemoteBuddy's Virtual Remote functionality), etc. etc. I'm so happy to be able to ditch my Apple Remote from my living so I can just keep it only to use in conferences with Keynote ;)
The only problem is that RumblePad consumes a lot of battery and needs charging quite often, like once in 2 weeks. I have a charger and a spare set of batteries, but it's boring to do...