Like several other respondents I would have to take a small library of cookbooks and even though I own over a thousand and buy new ones every day I would take the old battered classics, the ones that have good food writing as well as good recipes -any cookbook or all the cookbooks by Elizabeth David, Jane Grigson, Alice Waters and Paula Woolfert (especially her Moroccan and Mediterranean books) Marcella Hazan for Italian, Julia Sahni for Indian, Diana Kennedy for Mexican food, and Irene Kuo for Chinese. These books date back to when I was learning. The recipes are in my bones. I have a slight feeling of betrayal when I cook from someone else's cookbook which I do all the time. I've never been very good with general cookbooks. I relate strongly to the author/cook and how they write about a dish. David Thompson would be my choice for Thai food.And, Miriam Cunningham's Breakfast Book for my favourite meal of the day and Patricia Wells Bistro cookbook and Chez Panisse for desserts. And as for a new well used book I would have to say Sara Jenkins "Olives and Oranges". Then there are the books that make me hungry when I read them but from which I only cook infrequently, mostly British in fact but they write wonderfully about food - Simon Hopkinson, Nigel Slater and Tamasin Day Lewis. Hardly what you would call "travelling light"!