There are so many different, worthy, wonderful non-profits that would love to have your time. Some are easier to sign up for a single shift than others are, but then again, you should totally consider dedicating an hour a week with a friend for an extended period of time if you can.
During the school year, Holly and I volunteer at Marycrest Manor together. Even though its not the kind of volunteering where the two of us get to catch up, it provides us with lots of shared experience, later conversations, and a ministry we can pray for together.
The Denver Rescue Mission is another organization close to my heart. There easy volunteer shift sign-up is online, takes 2 minutes and has allowed me to volunteer grouping together canned food, making sack lunches and serving meals with friends and family.
I’d encourage you to spend a little time looking around or seeing if a friend might want to switch your night out at the movies or planned brunch for time serving together!