Steady on, Kay - I don't think Scott is suggesting pooling all of their resources immediately - and I don't think anyone would suggest that for a minute.
It sounds like, instead, you're looking for a joint "fun" account - somewhere where you can both chuck a wee bit of spare cash, for nights out, holidays, wee joint treats - that sort of thing.
I've got an account with Citibank that fits that bill - it has four linked accounts: Sterling current, sterling savings, euro current, dollar current. They're all instant access accounts, so the interest rate on the sterling savings is pretty rubbish, but it at least keeps pace with inflation. The exchange rate offered is pretty good - usually better than I can get on the high street, and with no commission. So, when I go to Europe, I transfer some of my savings into Euros, link my bank card to my Euro account, and then withdraw Euros from that account when I'm in Europe, so I don't pay any withdrawal charges or commission. Beats farting around with travellers cheques, safer than changing money before you go, and cheaper than being stung for commission every time you withdraw from a cash-point.
I happen to pay for this account - £10 a month - but that also gets me free travel insurance, free mobile phone insurance (albeit which only covers the wife's phone, as the iPhone4 isn't covered, which is a bit cack), and one of those "key and credit card" security number thingys.
On balance, I think it's a pretty good deal. In fact, looks like the charge is now only £8/month - less than £100/year.
http://www.citibank.co.uk/personal/banking/bankingproducts/currentaccounts/sterling/plus/index.htm?merchant=citi