Boxing. The best day of my life was the day I had the best sparring match (not experienced enough for actual amateur fights yet), where it just seemed like I was doing everything right, and making massive improvements on my skill. Unfortunately, I'll be moving back with my parents for summer break, so I won't be stepping foot in a boxing ring for a few months.
I've also been listening to the radio on the internet a lot, so I've been playing the Avernum series of turn based RPGs. Each of the 6 games in the series has a free demo, so I'll be occupied for some time

. The games have no background music, and since they're turn-based, I can listen to the radio and play at the same time without being distracted.
It's kind of odd for me to be playing turn-based RPG's, since I dislike a lot of things that are RPG staples (random chances, grinding), but the Exile series (of which Avernum is a remake) is a nostalgic memory from my childhood.
Furthermore, I've been really getting into Five Finger Death Punch. I was recently introduced to them by my MMA club (they sometimes play it when we train), and I tend to alternate between listening to the radio and Five Finger Death Punch when playing Avernum.