Magnetic/RFID without a third party.

Today I made a debit card purchase,
My card issuers website indicates "pending."
Are debit/credit cards any more instant than a Bitcoin transaction?

I have seen a few approaches to readily usable BTC.
They rely on 3rd party payment processors who provide equipment/fees.

I'm sure that with adequate client side security, zero confirmation transactions can be secure.

I would like to see open source development of such a technology for merchants to easily accept such payments without buying new equipment or paying extra fees.

I will now list some features that I think would increase reliability and safety of such technology,
1 Client-sided balance database for bitcoin addresses with balance/A way to quickly find the balance of any address.
2 The ability to search all unconfirmed transactions and identify a client who is attempting to double/overspend
3 The ability to send user generated tx's without the private key being revealed to merchant.
4 A low-tech credit card size device that can create transactions on the fly, without revealing the private key to the merchant.
There are many more features that would be useful, if you can think of some, share em.

Maybe this thread might inspire a competent developer group to attempt this project.