Currently I keep an obscurely-named text file on my hard drive which contains things like bank account and credit card details, various passwords, PINs, and other bits of sensitive/confidential information. Obviously this is not too secure and I'd really like to keep this information encrypted and password-protected. I'm thinking of something like Keychain Access, but for small amounts of free form text rather than just passwords, and it would need to be quick and convenient to access (i.e. so not something like a password-protected Word document). If it could work on both a Mac and an iOS device like an iPad, and sync between the two, then that would be a bonus.
I use 1Password. I a bit pricey but worth it. There are iOS and Mac OS versions. You have to purchase both. Where 1Password really shines is for website logins. There's a demo for the Mac on their site.
I use Acrylic's Wallet, works well on iOS and Mac OS.
I use, and recommend Splash ID which I have found to be very user friendly. For each "item" that you create (say bank account) you have 10 different forms that you can name the forms and put in whatever you like as well as a comment section which allows for much longer amounts of text. It also work on iOS ($10 from the app store I think). It's normally $20 but I found a coupon online for $10 off.
I believe it to be very secure, and it handles copy and paste really well.
I've had much success with Mac's inbuilt Keychain Access.