The eBags are essential for me to be able to pack and travel quickly and easily.  You can put suits in one bag, jeans and t-shirts in another, socks and underwear in a smaller eBag.  They help keep the clothes nice and neat too so they're not all wrinkled.  Instead of digging through an entire suitcase to find a shirt, you just pick out the right bag, unzip it, and pull it out without messing up any of your other clothes.  It's a MUST have!