Insightly Classic is the old version of Insightly. It's not available to new accounts. Users on Insightly Classic can switch over to the latest version.
Above every list of opportunities, Insightly displays the number and total value of the opportunities listed on the page. The numbers change dynamically depending upon which opportunities are in the list, so they will always update based on filter changes.
For example, you can create a custom filter to see how many opportunities you have with a forecast close date in the next 30 days and their total value. The helps you access quick totals for opportunities by user, tags, or any other field.