I dono if this will interest anyone or if it has already been found and posted, but I thought i may as well spread the word of this relatively useless bug.

Basically, if you have just restore your iphone or you have a large amount of music u want to change/add and you are not looking forward to sitting and waiting for your phone to be usable (i.e sync to finish), you can go into the SMS app and then press sync after a few seconds the iphone should crash to springboard and iTunes will still be syncing.

Now you are free to install apps, browse email etc.