There are even smaller homebrew QRP (low power) transceivers that will easily fit in an altoids tin (minus the battery), although I'd love a KX3. You need to know morse code for those to be practical, however. I'd also be, uh, slightly hesitant to bring a circuit board in an altoids tin through a TSA checkpoint.
And HF antennas are still going to be large, no matter what you do. Yeah, with enough loading coils you can get the size down a bit, but then you compromise efficiency. Physics is working against you for small HF antennas.
People seem pretty happy with their Buddipoles and Buddisticks. Those are decent-sized antennas that collapse down to something that fits in your carry-on.
And HF antennas are still going to be large, no matter what you do. Yeah, with enough loading coils you can get the size down a bit, but then you compromise efficiency. Physics is working against you for small HF antennas.