Marx thought that his utopia would be realized when the workers owned the means of production. Unfortunately for Marx, in his time the means of production that he focused on was the large factory with a relatively small number of large machines staffed by a large number of people ganged together in a collective enterprise. This forced him to think in terms of a collective social organization as necessary to achieve worker ownership of the means of production.

But Marx wasn't able to see beyond the means of production as it existed in his time. Modern factories turn the paradigm upside down: Large numbers of smaller machines staffed by a smaller number of people. I would posit that it's possible for workers to own the means of production entirely within the individualistic tenets of free-market capitalism.

I'm not the first to think up the idea of individuals owning "robots" (or specialized pieces of automated production machinery) and leasing them to factories; and living off the lease income. It's been done in several science fiction stories. To get there from here, imagine a manufacturer who installs automated machinery that necessitates a layoff of lots of workers. Instead of paying them severance, the manufacturer signs over title to individual machines, with a lease-back agreement. The cost of severance (including retraining, unemployment taxes, and the like) could be made to balance the lease cost; plus there are tax advantages to leasing.

But why even consider a hypothetical situation? Large numbers of workers today own the means of production: Information workers own personal computers. It's already proven feasible.