So sometimes my gmail in my mail folder updates instantly- faster than it comes in on my laptop. Sometimes, however, it takes hours before it recognizes I have a new email and I have to go manually into the html version of gmail to check if I have new email (even if I am connected to 3G or wireless the whole time). Anyone know a reason for this?

On a (probably) unrelated note, sometimes my N900 won't share images to facebook or via email and just times out.

Both of these problems sometimes go away on their own, and sometimes after i take out the sim card and battery. Thoughts?