Hi Millrythe,
I did the Pyramids and Nile Cruise last October and was so taken by it that I am doing it again this coming November.
For money I took around £200 worth of Egyptian LE just to cover incidentals such as drinks, snacks, souvenirs and the inevitable backsheesh (tipping) with the remainder of my spending money in dollars and sterling - both of which are widely accepted. The touristy sites Pyramids,Karnak etc will be crawling with vendors trying to sell you something you don't particularly want and these people admittedly can be a pain. Do not look at or acknowledge them and you will be fine. You will need a sun hat and sunglasses anyway due to the climate so these will serve well when you are ignoring these people. If you see something you do want however be prepared to bargain for it. Your tour manager will help you with this if you are uncertain.
Other than taking Wet Wipes, High Factor Sun and Aftersun Lotions,Anti Mozzi repellant and Hygenic Hand Gel (Egyptian Money is filthy) as well as a simple Medical Kit that's it. I did all this and managed to avoid "Tut's Tummy".
The trip is fabulous, the boat and the people were wonderful. The museum and sights awe inspiring.
Have a great time.