I’ve been working with cookies for the last couple of days, also known as a web cookie, browser cookie, and HTTP cookie (got that from Wikipedia). For some reason I always end up getting confused about what cookie is written where and how I get my code to respond to it, it’s simply never as easy as writing code when cookies are involved. Chris Pederick’s awesome Firefox Developer Tools go a long way to eradicating the hit and miss of deleting cookies from a session or domain, doing the same in IE or Chrome is nothing short of a nightmare. Firefox to the rescue, again (Just seen that Web Developer tools are now available for Chrome).
Whatever the working issues, cookies do allow us to manipulate our site to respond to users in different ways, which can be very powerful. Couple this with Google Analytics and we have a blinding set of tools for testing what works, with who and where. Again, very powerful. Also from a development perspective, the idea of making changes to a page and those changes staying with the user (without the URL changing) throughout their visit is quite satisfying, although not smug.