These are just some Ideas I can think of (Off the top of my head) for anvils.
- Repairing a weapon with it's base material will increase the weapon damage by half a heart. This can be only done limited times.
- Bows can be Repaired with string.
- Fishing Rods can be repaired with String.
- Items can be renamed with color codes. (&4Hello = [In Red]Hello)
- Shears can be repaired with Iron.
- Flint and Steel can be repaired with flint or Iron Ingot.