Great website, if you're sick of the texts and emails begging for money and want to actually get out there to GOTV in some way. Check it out, it will show you tons of events for your area or use the "Map" search to find out about events in other states:
@TheAbbotTrithemius
Mobilize is a great volunteer platform! We used it heavily when I was with DemCast.
They have something for everyone, like phone banking, postcards to voters, old-fashioned door knocking and more.
Some activities are general, even nonpartisan like GOTV, while others are party- or candidate-specific.
Being widely known and respected, lots of major volunteer organizations use them to facilitate their events, and to recruit new volunteers.