Can anyone shed some light on how to best save state in a web part.
Can I use a cookie or store a value in the viewstate?

Here's my problem, I've got a filter web part that I'd like to keep a
user-entered value upon subsequent page loads. Everything works fine
when the page is submitted or refreshed to itself, but if I navigate to
another page to add a list item or something, and then return. The
control just defaults to it's original state and not what the user
entered into the control.