The black sand beaches I've walked on feel much the same as regular sand and when its wet, it sticks just as well. But seriously, where do you go if you can't leave home. If I need the real warmth, I love to go to a sauna and just enjoy the heat. Have you ever been in a hot steamy room where you sweat the dead skin off and your body is all lightly flushed from the heat? I have and it feels so good.
The process out here is that you go to a nice hot sauna and enjoy some conversation while you warm up. Once everyone is ready, someone pours water over the hot rocks and fills the room with steam. You sit there till you can't stand it anymore and then slide down so you are laying on the floor, counting the minutes while trying hard not to be the first one out. When you can't stand it anymore, you run out into the dressing room where you cool off, drink liquid and talk. We talk about anything and everything. Its the equivalent to a coffee klatch
Once you are cool enough, you go back in and repeat the process. A typical steam can take anywhere from two to four hours depending on things. At the end, you wash your body and your hair using a bowl or dish pan so you are squeaky clean. I have gotten done, gone home and poured myself into bed. The next morning I got up feeling groggy and stumbled into work. They refer to that as a "Sauna Hangover" but it is worth it. At the end, your core is warm and you feel sooooooo good.