I have used honey, brown sugar, corn syrup, with a pinch of nutrients
I wash off the wort before pitching however
I prefer to keep some DME around for starters, but have been caught without it and had to go to the pantry for sugars. If you draw off the wort, (recommended method for any starter) you can use any sugar. What you are wanting in the starter is the yeast count to explode, for them to have strong cell walls and to be healthy and ready to attack the wort. Using DME is the recommended method, but basically for making a starter, sugar is sugar, we do not transfer the taste profile of the starter into our beer. Just the yeast slurry.
pitching the starter medium is just nasty.
let me clarify a bit
when we first start the process of making starters we normally just pitch the entire thing
then we learn to do a cold crash and pour off the medium, and pitch just the slurry
the next step after that is learning to wash the yeast so we get a more pure culture without the left over waste.
I digress