I think I've put this on here before, but anyway...
After my nan passed away when I was 15 I had her VCR (something sentimental, ya know?) and the tape left in the machine had the film 'Three Kings' on which my nan had recorded off channel 5. Straight after the film the tape had continued to record the usual late night soft-core stuff.
Anyway, I wasn't bothered by Three Kings and taped over it with Forrest Gump. A few days later my mom was talking to my mate who lived over the road from me and the conversation somehow got round to talking about how Forrest Gump was on the telly the other night and how his girlfriend had never seen it. My mom told him I'd recorded it and to come knock our door later, I could lend it him for them to watch.
Him knocking the door would be the first I knew of this and I panicked because I knew him and his girlfriend would watch the film and then as soon as it's finished the soft-core porn would start. I told him I didn't know which video it was, to give me 20 minutes and I'd run it over to him when I'd found it. I recorded 20 minutes of Kerrang TV at the end of the film to tape over the shitty porn.
Next time I saw them both, his girlfriend said 'We know why you took so long to bring the video over, you were taping over your porn.' to which I responded 'Nah, it was my nan's video'. They still don't believe me.