Love them or hate them, musical greeting cards will almost always bring a smile to someone's face, and the smile might be widened a bit if you create your own music and card. Blogger Jarv shows his easy method to making the music happen.Using an ATtiny85, a cheap speaker, battery holder and battery, the build comes in under $US5. The music is created in Musescore, a free composition and notation program. If you don't fancy yourself a composer, there's also a guide to importing MIDI tracks into the program and simplifying them for play in your card. You'll need to construct the card yourself, but if you've always want to blast a MIDI version of Warrant's "Cherry Pie" in a greeting card, this is probably your only chance. You can find the guide and codes over on Jarv's site.