His bills are my bills and my bills are his. When we got married, his debt became mine, and mine became his, so there is no need to keep separate accounts for our "own" bills. Therefore, one checking account from which all bills are paid, with remaining funds being distributed among 2 savings accounts, which we can both access for whatever we need.
We each take a set amount of cash each pay for daily expenses, such as lunch or gas money. As for the savings accounts, one savings account is for those things that might come up between pay periods that our "allowances" don't cover. When the funds in that account reach a certain, mutually agreed upon, dollar figure, everything else goes into the other account, which earns a higher rate of interest. Withdrawls from that second account are usually for big ticket items and are discussed and agreed upon before the money is taken out.