Most of the hotels and travel agencies in Hurghada organize one day excursions. If you have not visited the rest of Egypt it is possible to do a one day trip to Cairo (i recommend to spend two days there at least, though) and to Luxor (idem).
I do recommend to do a one-day excursion to the desert with a jeep. Most of these trips visit the Roman sites: Mons Porphyritis and Mons Claudianus. Another great excursion is a visit to the Saint Peter's and the Saint Anthony's Monasteries. You can also do a half-day excursion to the desert, where you can ride a camel, eat a bedouin dinner and witness the sun set.