I assume it is the link Fun Arcade in your sig. Per click return really is out of your control. You can only improve the traffic but not the per click revenue.
In my experience sites that are for general audiences, such as jokes, games and entertainment, tend to have lowest per click revenue.
Sites that are more market focused, like money, health, business, travel, etc, tend to do much better in return per click.
I see this difference when I compare my World Cup site with my travel sites. There is definately lower per-click revenue on the sports site.
At the same time I noticed on my sites that sometimes a click generates $1+ and another time a click on the same page generates only 0.02-0.30. So it seems to indicate that there is a mix of advertisers: small and large.
It could be a slow time for large advertisers on your particular niche.
Why not focus on developing other sites in other markets. Let the arcade one rest and see if it generates higher ppc revenue in the near future.
Hope this helps.