We get heavy use out of the grid filters, and we would like to see more advanced grid filtering options, including:

1. For number filters, ability to use multiple filters together with an OR, such as (X < 5 OR X > 10) (but to still be able to choose to use the default AND behavior)
2. For all filter types, ability to do not equals-- for example X != 10 or Name != "John"
3. For string filters, ability to add multiple filter conditions to a single column-- for example (Name LIKE "John" OR Name LIKE "Jack")

We do most of our filtering remotely, so it is possible to implement these complex filters on the server side, but the challenge is creating the UI for accepting more advanced filters.