I did this to my friend when I was a Senior in high-school, and I'll never forget it. Lets call my friend Rick, and this girl Ashley.
I would say that Rick was a pretty popular kid at this point in his life. Throughout high school he dated a lot of girls, probably more than he should have. This one girl in particular, Ashley, was a really close friend of ours who lived in a neighborhood over from mine when I was a kid. We all remained good friends throughout our young lives, but she never thought of Rick (or me) in a romantic way. She was gorgeous and popular, always smiling. She had just gotten over a rough breakup, and I tell that her heart was aching. Rick and Ashley were both going to Michigan State University next fall, and quite honestly I think he was done having girls in and out of his life. He told me he wanted a "full commitment", and he decided he would ask Ashley out. I really wanted to help him tell this girl how he felt, but we had no fucking clue how to do it. He had to word it just right, to truly explain how I felt about her. It was 2007, and we were browsing YouTube ---- and then it suddenly dawned on us.. he should make a music video explaining how he felt. Rick was a decent singer and decided that it would be best if he wrote her a song, since Ashley was involved with the school choir and loved music. After a week or two the song was complete. We filmed a shitty music video and saved it on my computer. Rick had been flirting with Ashley, but this video was to "seal the deal." I went home after we filmed the video and for no good reason I decided to troll the shit out my best friend. Rick still had his e-mail logged in on my computer. I pulled up a confidential video of him at a party, extremely drunk, making out with Ashley's sister, a sophomore in high school at the time. This video was taken last year, before Rick had any intent of dating Ashley. I sent it, with the message "LOL, THIS IS HILARIOUS" or something douchebagish like that.
Ashley walked up to Rick the next day, slapped him in the face, and never spoke to him again. Rick never sent the real music video. I still feel horrible about it to this day, and Rick and I are no where near close friends... He moved away, and I haven't spoken to him in months.
This is the music video that Rick made.