I would like to argue that Collision Course, their mash-up album with Jay-Z (who I believe now goes by Jay Z) is the last cool thing Linkin Park has done. Much like Backstreet Boys, and a number of other musical groups from the late 90s/early 2000s, the sound of their music mellowed as they aged.
This album was perfect for angsty 15/16-year olds – there was something for every angsty problem. Sometimes in our free time, my high school roommates and I would throw this on, because it was a perfect blend of the rock music I liked and the rap they liked. Bouncing around the room we would sing along with the music, using whatever we could find as a microphone.
I recently re-found this album in my iTunes, and have been returning back to it on and off a few times over the past couple of weeks while walking around town. If you have not, you really should check out the whole album.