I’m still waiting (in vain, I’m sure) for handwriting recognition, à la the Newton, but until then, it *is* nice to have a good choice of styli: iPad stylus buying guide: Find the perfect tablet accessory.
Keep snooping relatives out of your stuff? It’s really simple: don’t let them use your equipment! If that’s not an option, don’t let them use your account on your Mac. Dr Breen and various commenters lead an interesting discussion on the subject.
If you’ve got as many PDFs on your hard drive as I have, and you’re using Mavericks, How to add your PDFs to iBooks and organize them will prolly be a boon, especially if you’re not using Delicious Library.
For the whole shooting match, PYBT: Macworld HELP DESK 11.29.2013