Everybody knows that one of the more challenging things about traveling with a baby (apart from trying to keep the baby happy...) is trying to fit all of the baby's stuff into your luggage.
It is worth getting travel size versions of whatever you can. Beaba does this very cute folding travel bath which takes almost no space in your suitcase. (http://www.beaba.com/flash/#/en_GB/products/details/73-122-Folding+Baby+bath).
A good investment is also a travel size steriliser. See, for example, the one from Babytec (http://www.babytec.co.uk/electric_steam_steriliser.html).
Baby Bjoern does a very compact and pretty light travel cot (http://www.babybjorn.com/us/products/sleep/travel-crib-light/travel-crib-light/).
If you have the Bugaboo, the Bugaboo travel bag is great at protecting your pram as well as providing a bit of additional space for baby stuff without counting towards your flight baggage limit...