Eric von Hippel of MIT has charted the phenomenon of user-led innovation, and how this has benefited both companies and users, in The Sources of Innovation , published in 1988, and, most recently, Democratizing Innovation* .
As discussed in the ‘Reactions’ section of this site, whilst the trend for users to modify and tinker with their products to improve them or create new functions does not yet appear to have abated in an age of increased architectures of control, there is reason for concern–von Hippel notes, with an interesting example, that:
“Current efforts by manufacturers to build technologies into the products they sell that restrict the way these products are used can undercut users’ traditional freedom to modify what they purchase… Makers of ink-jet printers… may add technical modifications to their cartridges to prevent them from functioning if users have refilled them.
This manufacturer strategy can potentially cut off both refilling by the economically minded and modifications by user-innovators that might involve refilling… [such as refilling] cartridges with special inks not sold by printer manufacturers in order to adapt ink-jet printing to the printing of very high-quality photographs. Others have refilled cartridges with food colourings instead of inks in order to develop techniques for printing images on cakes.” 
Refilling Canon inkjet cartridges with food colouring and printing onto edible paper has allowed companies such as Sugarcraft to open up a new field of cake decoration–user-driven innovation of the sort which could be threatened by increased use of architectures of control to prevent product modification. For example, if printers that can detect refilled cartridges and hence refuse to print become more common, Sugarcraft’s business model may be threatened. Equally, one can imagine a printer which can force the user to use only the manufacturer’s own brand of paper, perhaps using some kind of non-visible code printed on or embedded in it. Such economic lock-ins are hardly new–it’s just that the technology is now easily available to permit them to become much more common.
It is not unlikely that future studies by von Hippel or others working in this field will document ingenious user innovation in spite of architectures of control; the challenge may be a sufficient lure in itself for some technical users.
*I have retained the US spelling for this title