Types of popular one page sites?

Hi guys.

I was wondering if you know types of sites with one single landing page that are popular. As an example ip lookup sites. I want to create a single landing page that would offer some kind of service to the users, so that they come back on a regular basis. If you know or have any ideas about such sites, please let me know. Thanks!

 

Something like this?:

http://fuckinghomepage.com/
http://www.rainymood.com/
http://www.patatap.com/

 

Not exactly, something where the user checks for something, like ip lookup site, messenger invisible/offline check, whois domain.... sites like these.

 

Rainymood plus smooth jazz plus a crackling fireplace 8 hour loop is such a relaxing way to get work done.