I'm using Raiser's Edge to track our grant deadlines. We're calling our foundation/government entities "constituents." 
I tried to add a due date to my Google calendar from RE and it showed up as "Task/Other" vs. the Constituent's name (i.e. Love Family Foundation) and Action (i.e. final report due).  This would be a great thing to add in the future so that I don't have to then edit each "Task/Other" on my phone's calendar.