I’m using a free organization account.
I created a private “Follow-Up” project specifically to track things I’m blocked on or need to follow up on.
If a task I’m working on becomes dependent on someone else for something, or if I can’t work on it right away, I’ll add the “Follow-Up” project to the task (while leaving any existing projects as they are). I also set a due date for the task for when I want it to show back up in My Tasks under Today. Then I mark the task for Later (TAB+L from within the task) and it goes away off into the Later section of My Tasks and won’t bother me again until the due date arrives.
The Follow-Up project also gives me one place to go to see all the things I’m personally waiting on across all projects. Because it’s a private project it doesn’t clutter up the team’s project list for other team members.
I also use the “Reminder Tasks from Inbox” and “Follow-Up Tasks from Right Pane” hacks in my profile settings to easily create follow up tasks. I always use the same procedure for these by adding them to the follow-up project and setting due dates. This allows me to check in on things that maybe aren’t assigned to me but need my input, or something I want to go back to and comment on later but don’t have time to currently. This way I don’t have to leave things in my Inbox when I know I want to respond and I can prioritize them in My Tasks based on when I want to deal with them rather than having them be a full interruption.
Let me know if you have questions or want more specifics.