Preschool Websites

If you have a letter obsessed preschooler in the house then, I highly recommend: Starfall

We have only been playing this website consistently with Sam for a few days and he already can do it by himself.  The ABC section, which we use the most, is for letter recognition and sounds.  It reinforces the recognition of letters that he already has while helping him master sounds.  At the same time it uses some sight words.  It's great for the (older)2-4 year old range.  We have a touch pad mouse on our laptop and I was skeptical as to whether he would be able to master it or not but of course he did!  I think* he even taught himself to click and drag today...
(*Confirmed - He did in fact teach himself.)

There is also a section for older kids that has stories and works on combining letters to make sounds.  We have been exploring this a bit with Sam.  He likes the "ar" story called, "Car Race".

Best of all this website it completely free and doesn't have a bunch of annoying pop up ads!

We also love:
Tumblebooks which isn't free but we are able to link to it from our library's website and then it is free.
PBS Kids for their games.
Since my college days I have been a fan of Kinderart.

What is your favorite kids website?