Answering emails regularly is getting to be important. Inevitably some emails are getting lost on the Inbox List. Here's a way to mark an email for follow-up later:
1) Right click on an important email
2) Select "Follow Up" from the list that appears:
3) In the next window choose "Follow Up"
4) In "Due by:" select the date when you need to follow up, on the drop down menu next to that you can select a specific time when you need to follow up.
5) Click "OK"
On you Inbox list the email you have "flagged" will now have a little red flag next to it. When the due by time arrives you'll be reminded of the email again.