Sorry, you have no messages! Do you know how nice that is actually to see? Some say I may have cheated on getting my inbox cleaned out ... as I took advantage of Gmail's search function and archived my entire inbox! First though, I answered all messages from the last three days that needed answered, filed the ones that didn't, created filters for the ones I want to read when I have extra time (so they never sit in my inbox!!), and unsubscribed to those items I just don't care to see!
Once in a while I get on a cleaning kick - and I personally find it much more "fun" to clean up my "electronic" files...now I just need to get to those filing cabinets! (the non-virtual ones, sitting behind me :)-)
As you have slower days during summer and find it hard to do "actual" work, take a few moments to create folders and filters on your email. You'll be happy with the quality of emails that end up in your inbox - those ones you actually need/want to receive and you will free up time to go do something fun!