Not without the express consent of your giftee. If you are interested in hand delivering a gift, please contact your giftee (you can do so anonymously from the retrieve match page) and ask if that's ok with them. They may be more comfortable meeting at a local coffee shop or somewhere more public than at their house, but if they're ok with it, it's ok with us. Just remember to mark it shipped, and you can use "by hand" as your shipping method.
It is one thing to know you have a parcel coming from a stranger on the internet, it's a whole other ball game if they show up unannounced on your doorstep. Absolutely do not hand deliver a gift without the express consent of your giftee. Doing so will cause you to lose your eligibility for all future exchange participation.