I pledge 100$ to the following cause:
In Listbuilder I want to have a switch that allows me to hide / show a group of entries (just like forums allows you show / hide threads). The switch should be a boolean that just determines "yes, I want listbuilder to show me the list with dynamic show / hide" as described below.
The groups that can be shown / hidden are determined by the orderby value run on the list, so you group the list by the entries that have the same value for the $orderby column. A show all / hide all button should be available as well.
Where is this useful:
I have a list of tasks. If I order the tasks by company_name, I can show / hide the tasks of companies I don't want to work on right now. Same is true for ordering by project. If I order by deadline date, I could only work on those tasks where the deadline was yesterday, hide all the rest.
Note: Do not make things complicated. If I have pagination turned on and only show 30 entries then do the grouping on those 30 entries and do not change the total list just because I hide / unhide a group.
As always the first committer to CVS can decide what I should do with the pledge.