Web pages with multi-page listings of things where you must scroll to the bottom of the current page only to find out that the entry you are looking for is on some following page, causing another click, and repeat until you find the page that contains the item you want.
For example, go to the Community -> Member List, click R looking for Rustward and go at it. You'll find him on page 28. If you did it the hard way, you would have scrolled down to the bottom of 27 pages, then clicked on the next page number, scrolled down until you saw Rustward. But most people would have skipped some pages, which becomes a hit-and-miss proposition.
If the key (user name) of the last entry on the page were displayed on the top of the page, one could make the decision to page forward without having to scroll down to the bottom of the page.
[In the mainframe world, which happens to be still very much alive, this would be called a "search key greater than or equal" -- done the hard way (manually).]
Or, an alternative: When I click on the R, show me a page that contains a clickable link for each of the "R" pages, along with the highest key (user name) of each entry on that page. Then I can find the page that would contain the user name I am looking for (if it exists) and go directly to that page.
But this is still a manual search. These computers were invented to work for us, not the other way around.
Even better: How hard would it be to implement a generic search? Not talking about wildcard characters (but those would be nice). Give me a box and let me enter the starting characters of what I am looking for. Entering "rus" would position me on "rusnkaz", which is 16 entries above "rustward". But if I take all the effort to then type a "t", I wind up on rustward's member list entry.
I used the member list just as an example. There are lots of places where this could apply -- and some websites do this. It may be worth it only on lists that have the potential to become very long. For a list that might have a maximum of 10 entries it might be overkill.