Chase Cash Rewards - 1%
Citibank Dividends - 1% up to $300/year
REI (US Bank) -1% other purchases, 10% REI non sale purchases - issued as a dividend (can be used like a gift certificate for purchases the first half of the year, turned in for cash later in the year)
I try to put almost everything on credit cards. I pay my insurance, groceries, pretty much everyone that takes credit cards without a surcharge. I used to work for a small company where I could buy computer equipment on my kickback cards, get reimbursed within a week and collect the interest for a month before I had to pay the bill. That's how I found the previously undisclosed $300/year limit on Citibank's card.
The trick is that you have to have great credit to be eligible for the cash kickback cards. They basically give you the 1% because they know you're going to pay your bills, so it's a good deal for everyone. The Citibank card I got by a fluke. You can try the same tactic, but it won't always work. I called to cancel my card and they passed me to a retention specialist (someone whose job is to keep your business) and they asked me why I was getting rid of the card. I told them I don't use it because I get cash kickbacks on my other cards (this was true, but there is no way for them to verify this) and had much higher credit limits on other accounts. They upgraded me to the Dividends card and substantially increased my credit line.
Another tactic if you've got enough self control to not drown in debt is to use cards often enough that they will give you a low rate balance transfer option and then sit on the money and collect interest. You have to factor transaction fees and offer expirations into calculating who is sticking it to who in this game. I've got a couple that I'm currently abused for fixed low rate until paid in full. I'm making more in savings than I am paying in interest, so it'll take a while for them to get their money back. If you do one of these, make sure there's nothing autobilled to the account and lock it away until it's paid off. If you charge anything, that collects interest at the purchase rate, which is higher than the promotional rate. Your payments go towards lower rate balances first. They're counting on you to not do the math and end up paying them more in interest. Unless you're really careful and can set the account aside for a long time, don't try to take advantage of these things. A lot of people drown in debt by thinking they have a ton of money in the bank, without considering the debt that got that money in the bank.
Also, if you have a balance transfer that has to be to another credit card, you can take advantage of those too. If you have a credit card and checking account that are available in the same online banking account, you can probably do a transfer from the credit card to the checking account. Do a "balance transfer" to the credit card, then do a transfer to the checking account and you can stick that money wherever you want without having paid for the privilege of turning a "balance transfer" directly into cash.
If you eat out with friends or otherwise go places where most people pay cash and there are significant bills, put the whole bill on your kickback card and pocket the cash. I refer to this as "cheating" because you're getting a cash advance that's charged as a purchase. Just make sure you have the money at the end of the month to pay that bill. This is a great way to avoid going to ATM's. It's a stupid way to get extra money to pay bills.
If you have self control and a firm grasp of how the banking industry works, you can build great credit while netting a fair bit of change yourself. You're not going to get rich doing any of these things, but you can stick it to the man in a small way and make money at it.
Does that answer your question about working the system?