I was thinking of putting some sliders in my kitchen cabinets and stumbled on this at walmart. Depending on how well built they are. This could be a better solution. Its on sale for $33, I was looking at $30 in materials to build my own.
http://www.walmart.com/ip/JA-Marketing-99-WOOD-Shelf-On-Wheels/33361449
Also this one in metal for $37