Hey there,
In your projects table rollup the due date field using the formula min(values). Use the filter option within the rollup to filter out completed tasks.

In Tasks table do a lookup of the due date rollup field

Also, in your tasks table use a formula that looks if the due date is equal to the rollup field and if it does, display the task name.

Finally, in your projects table, do a lookup of the calculation which I labelled 'next task'
Hey there,
In your projects table rollup the due date field using the formula min(values). Use the filter option within the rollup to filter out completed tasks.

In Tasks table do a lookup of the due date rollup field

Also, in your tasks table use a formula that looks if the due date is equal to the rollup field and if it does, display the task name.

Finally, in your projects table, do a lookup of the calculation which I labelled 'next task'
Thanks Zack - and I appreciate the helpful screenshots!