I work from home too, so this has been on my mind as well. I don't think it's going to be a question of how to fill my time so much as what to let go of because priorities shift and time can sometimes feel scarce.
With my first, I took 5 months off from work and 8 months off from school. Even in that scenario feeding, changing, washing, and napping took up pretty much all of the day...and night. I'll echo the others on babywearing. That was the best both for getting out and doing what I needed/wanted to do away from home, as well as getting things done at home in small chunks. I literally remember breaking down the task of "unload the dishwasher" into 1) unload top shelf, 2) unload bottom shelf, 3) put away silverware; and those three steps might take me all day, lol. The first few weeks were an absolute blur. But within a month or two we had a new "normal" (which was NOT the old normal in terms of productivity, that's for sure!). Actually I found it easier to do things with a little baby vs one that was crawling/walking. For a few months there, they'll chill in a sling or lay at your feet on a blanket. I have some really fond memories from my maternity leave of strapping DS on and heading out to do things that I loved but never had a chance to do while I was working/studying; things like going to museums, volunteering, and visiting friends. I got a lot of sewing and crafting done too.
Now, expecting my second and working from home, my vision is to take 6-8 weeks off of work to heal and find our rhythm. Then I plan to get back to work with baby on my back. I work 10-20 flexible hours a week and even with that schedule, I expect that it may be interesting to find a lot of usable work hours in a day given that, as others have said, the day is broken up with baby care every 1-2 hours. But I think I'll manage. Once baby is crawling, we'll probably need childcare of some sort in order for me to work from home. That might be a co-op situation with another mom or a nanny share or something else.
You'll figure it out ;)
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