The pillow above is from my collection from my Etsy shop. It can be found at http://etsy.com/listing/46603953/blue-and-white-pillow. This airy pattern is beautiful and soft. It embodies exactly what I think Blue & White should look like.
I think that when people put together a blue and white room they feel obligated to stick with blue and white only. This is a clean and classic look but you can also have some fun with it by adding an unexpected color here and there. By doing so, you should probably treat the blue and white as your neutrals and add a splash of color in your accessories, pillows or find a fabric pattern that has blue, white and your third color. For instance, a beautiful burnt orange is the perfect ingredient to a sophisticated and fun room. Other colors that can be fun are raspberry, apple green, or play with different type of blue (teal or turquoise). This can also be applied by having a fun bouquet of flowers while entertaining.
This idea is nicely incorporated in the triangular tile from Country Floors above arranged in a hexagon pattern. As you can see, the blue and cream are the primary colors where the green and orange / red are the unexpected pop of color. This is available through http://www.countryfloors.com/ and is also from the Crossings collection "Andalus Triangle".
These charming plates are found on www.wisteria.com and are called "Spanish Inspired Ceramic Tapas Dishware - Blue Plates W3520" $39.00 for a set of four. These plates would be nice addition to your dinner setting by adding a bright color napkin or playing with the floral arrangements. Also, these plates would be great hung on the wall either alone or with another color plate.
This spectacular vase is from fellow Etsy seller "Muddman". It can be found on http://www.etsy.com/listing/46128553/decorative-blue-crystaline-vase. It contains many shades of blue and darker blue crystals running along the entire vase. It would make a great addition to a bookshelf or any other occasional furniture piece.