There are many Irish records available from the LDS.

Have you checked your local FHC to see what Irish films might be on indefinite loan? That's how I got started on the 1864 All Ireland Birth Index. I searched the web and didn't find this online anywhere. I found numerous surnames for the birth index online, but only small sections of a particular surname could I find.

What else is at your FHC? If you find other smaller projects that you would like to work on for County Cavan, Ireland, or for other Irish counties, I'm sure the Coordinators for those counties would love to have you do some work on those projects for them.

How can you make a difference for others who have helped you? Go to your local FHC and see.