By savings, I mean like... £4000.

If there is no easy/cheap way of doing it I guess I could take it on my carry-on luggage with me.

Absolutely use Custom House. They give the best exchange rates, and don't charge for electronic transfers. I've used it for both large and small transfers. The staff are extremely helpful and very pleasant and professional..... even with idiot questions. 3 day transfers cost nothing.... same day transfers cost $20. You can transfer from your UK account to your US account, and vice versa. They're absolutely wonderful.

Just use one of the currency exchange kiosks an any airport...

JUST KIDDING!

Seriously, customhouse.com or xe.com (different websites, same company)

...

Would this also be okay to use when transfering amounts over 10k? Not the kind of thing we want to drag around with us in airports!

My wife converted her savings into about $15,000 worth of traveler's checks and brought them with her. Once she got here, we deposited them into my account, no problems.

Check for ikobo or some money transfer places online. You can get good rates.

Yes, amounts over 10k are fine.

The one thing you do NOT want to do is bring any amounts in foreign currency. The banks here do not know how to handle it. But if they do, they will charge you an arm and a leg in currency exchange and service fees to cash it, so it's not worth it. And, after one year, I am still fighting to have a valid Canadian cheque reissued because my bank here entered the wrong coding and the bank in Canada rejected it. So not only do I not have my money, I was charged a service fee for a returned cheque and I cannot get them to take responsibility for it!!!!!

Oh.... you'll also want to see one of Mr Fancypants threads to see what they had to go through to cash a cheque from Ireland. Absolutely ridiculous.

I use www.interchangefx.co.uk
Rates are pretty good, they can be a tad pushy though lol!

But they gave really good rates and the account is simple to set up.
Would advise setting it up before you leave the UK though since they want bills to prove your address.

Your post reminded me that, with Custom House, you choose the exchange rate you want to lock in at. Basically, it's like playing the stock market, because the rates fluctuate throughout each day. You can be notified when it hits a certain "buy" point or you can choose the current rate. Or you can just watch the rates go up or down and lock in when you see something you like. And, as I said, if you don't understand it, they are so friendly and understanding in walking you through it and explaining everything.

I used InterchangeFX and they were good.

Another satisfied Interchange customer here.