I was in Egypt in November. In the main, I brought US$ traveler cheques (yes, I know, how antiquated!) and Egyptian Pounds. I also brought a few US$ in cash and needed them as soon as I arrived at the airport to buy the tourist Visa (US$15). Single dollars are very useful as tips.
A lot of the fixed price shops and tour companies quote prices in US$ and accept them for payment.
If I were going again, I'd bring more dollars and fewer Egyptian Pounds!