I know bitcoin supports easy creation of new addresses and you can have a unique address per transaction but I'm wondering about the feasibility of such and how it could be done transparently. You have two costs associated with having multiple addresses. First is the transaction costs of your time in setting up and managing multiple addresses and secondly the fee paid to miners when funding your address with the appropriate transaction amount. Also, while having individual addresses for each transaction might obfuscate the consumer at the transaction level from merchants linking accounts, a merchant could certainly dig just under the surface and see that if A sent .53BTC to X1 and X1 paid the merchant .53BTC for one transaction and then in another A sent .21BTC to X2 and X2 paid the merchant .21BTC in a second transaction, both transactions are most likely the same person.
I have an idea for one way around it but it requires a 3rd party. Any other ideas?
Its very easy in bitcoin wallets I know to create new addresses. Not sure what problem you are trying to solve. If you want a new address for every transaction, you just do it. If you don't, you don't.