Here's a great idea for Valentine's day! It's much more creative then simply making a plain card for your boyfriend, friends, loves or husband/wife.
I'd use this video tutorial (for making a pop up "book of shadows" - like the Urban Decay Alice In Wonderland themed one) as a guideline and get creative to make a pop up card that will be more personalized depending on who you're giving it to. Maybe even try and do a pop up of cupids or hearts?