What would it take to recharge your laptop and other electronic devices by riding your bike? There are highly efficient and reliable dynohubs these days. You could mount a small lead-acid gel cell battery on your bike and charge it by riding.
A regular car or motorcyle battery holds in the tens of kJ up to MJ. The Wikipedia article for "Car battery" says 30–40 Wh/kg, around 100 kJ/kg. My netbook battery says:
$ acpi -i
Battery 0: design capacity 5246 mAh, last full capacity 4518 mAh = 86%
It's, I think, 11 volts at the moment, which means it had about 200 kJ when full. So you'd need about 2kg of lead-acid battery to hold a full recharge for it, plus some small, lightweight electronics like a buck-boost converter to supply the laptop with the 19 volts it wants for recharging.
Amazon has a £17 lead-acid battery with 10Ah at 12V, or 400kJ. At the moment £17 is US$27. (Typical prices seem a bit higher.) It weighs 3.3kg. If everything scaled linearly, a 200kJ lead-acid battery would weigh 1.7kg and cost US$14.
At a substantial cost in reliability, safety, and money, you could use the laptop battery directly. I think it weighs more like 500 g, but it costs more like US$100.
A bike dynamo hub like the Schmidt SON28 consumes some 2–6 W of mechanical power, and probably has efficiency in the 80%-99% range. Getting 200 kJ out of 4 W would require almost 14 hours of riding, which I think of as two to four days' worth.
A modular display strategy would be very useful: several cellphone-style displays would both be easier to protect against breakage and allow scaling power usage up and down as needed.