Solution's up there:
Basically, the issue is that the latest version of Flirc relies on a newer version of libusb than the one shipped on most distros. As a workaround, you can download, compile and install libusb yourself, and force Flirc to use that instead.
For ubuntu users (tested on precise/elementary luna):
Download libusb from here, extract it, open a terminal and cd to that folder to compile the lib:
$ cd <path_to_libusb>
$ sudo apt-get install build-essential libudev-dev # You'll probably need these if they're not installed
$ sudo make install
Once that's done, cd to the folder where you've extracted Flirc and run the program by overriding $LD_LIBRARY_PATH to point to where the newer version of libusb got installed:
$ cd Flirc-v1.2.2-x64
$ sudo su
# env LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local/lib/ ./Flirc
Flirc should now start without issues.