Thanks so much for your speedy replies!

Kazbah, I think the brown sugar in water might be something she'd take to- she has a bit of a sweet tooth already I'll try that tomorrow. At the moment, her idea of "choosing" her own cup is to take home all of them :P She's very entertained by cups, loves to carry them around, but has a super short attention span when it comes to actually drinking from them.

Katie, the straw cups have been the most successful so far for us too. We've tried a range of diluted and even undiluted fruit juices, but she's still not all that keen- apple juice today was more successful than usual. I gave her some Milo last week working on the same theory as you (any fluid is fluid!) but that got the veto, too. Maybe I should move onto Coke or Fanta next (kidding :P). Thanks for the pointer about bran, too- that might be part of the problem, ironically.

Kitten, she used to have porridge for breakfast and liked it. Thanks for the reminder- I might start giving it to her again. And I was just thinking about soups today- definitely a good idea. I've been giving her jelly and watermelon and things with high water content on occasion but for some reason hadn't thought of soup.