While browsing the web, I came across this cool site which has over 200 data-models samples.
Great for anyone who wants to learn about data-modelling or have a template for a given problem domain.
The link is here : http://www.databaseanswers.org/data_models/index.htm
Some interesting data models I found in this site are - datamodels for Hierarchies , e-commerce etc. Worth a perusal.