This is in preparation for a medical procedure (that I'm NOT looking forward to) so it's all temporary and I'm not too worried about it being well-balanced.
Make really good homemade stock.
You can eat quite a few foods on low fiber diet options. http://www.stopcoloncancernow.com/buttseriously/prevention-info/pre-colonoscopy-diet-could-be-more-indulgent-than-you-think
You can make clear chicken stock or broth (strain it through a cheesecloth-lined colander if it must be absolutely clear; you can also have it as chicken-in-the-pot with rice or noodles and the chicken pieces, removing the vegetables to avoid fiber). You can also make a very tasty vegetable stock (use shiitake mushrooms for extra depth of flavor, along with the usual suspects, like onion, carrots, celery and garlic)--again strain if it must be perfectly clear. Are you allowed red juices? Cherry juice (either sour or sweet) is delicious and healthy. If not, the Ceres line of juices are very tasty and also relatively clear and they have several varieties that are light in color. You can make frozen popsicles from juices too if you have a mold (just for a change of pace). Or maybe some gelatin-based foods (sweet or savory) for variety.