They are probably one of the most popular trend in Web 2.0 time. It's most over-used trendy little design technique in our days, they immediately attract visitor's attention. Web badges have various round or square corners and eye-catchy colours. Badges can be used to display a big 'Beta' message on your website or emphasize a price or a promotion.
No web 2.0 site is complete without one.
Read more: http://www.web20badges.com