The problem isn't a lack of software to put on hardware, it's a lack of hardware that doesn't go out of its way to thwart attempts to install different software, either intentionally or as a side-effect of being optimized for cost.
As an example of the latter, I have a Monoprice-rebadged Tenda W301A ceiling-/wall-mount AP on my desk. It only has 2 MB of flash and 16 MB of RAM. It has a TTL serial port, but the lines are broken out to surface pads that aren't even grouped together on the PCB. (They're not labelled on the silkscreen, either.) The version of u-boot it ships with is stripped down to nothing, probably because of the limited flash space available. For ≤$5 more on the BOM, these problems could be fixed, and the device would be considerably more useful.
There are devices with more RAM (32MB or 64MB) and with USB port(s) where you can mount a flash drive / external disk and install anything (like Transmission, or even Samba) on it and use as a poor man's NAS. For example the TP-Link MR-3020 is pretty much hackable [0].
As an example of the latter, I have a Monoprice-rebadged Tenda W301A ceiling-/wall-mount AP on my desk. It only has 2 MB of flash and 16 MB of RAM. It has a TTL serial port, but the lines are broken out to surface pads that aren't even grouped together on the PCB. (They're not labelled on the silkscreen, either.) The version of u-boot it ships with is stripped down to nothing, probably because of the limited flash space available. For ≤$5 more on the BOM, these problems could be fixed, and the device would be considerably more useful.