MicroSD shield from Sparkfun.com . I thought it would be just as easy and hooking up a few wires and bam I'd be saving away on the card. Well it should have been. But I struggled all day with this. I could get it to recognize the card, finally I was able to write to the card with the library that sparkfun had on their site. However I couldn't read to it. I found all sorts of great libraries for FAT16 file systems out on the internet, but most had the wiring to the arduino done differently. Even if I went into the code of the library to change the pin setup it still wouldn't work. I couldn't understand why sparkfun had the final pin to the micro SD holder go to pin 8 instead of 10 like everyone else. So this morning I rewired the shield to my arduino and low and behold we're writing and aving info just like that. Almost made yesterday worth it, almost. I wouldn't hesitate purchasing the shield from sparkfun I would however be aware that it isn't going to sit properly on top of your arduino. You'll have to think of some other wiring system.