Hi Johannes - you were asking about my solar charger. It's a commercial product, the Global Solar Sunlinq 6.5W (ME² Solar in Europe). It's a folding design, with 4 solar panels mounted on a rubber-like pad. It doesn't have a weight saving over your Solio - mine is 255g (9.0 Oz), but it has the advantage of having a 12V car charger (cigarette lighter-type) connection so it's suitable for many devices, as well as having a fairly hefty 6.5 W output (I think the Solio is less than a Watt). It doesn't have a built-in battery, but I believe Global Solar do have equivalent models with one - my phone's battery was of too high a capacity to make use of the battery though, so I got the basic (lighter) model without a storage battery, and connect it straight to my phone. It works very well, taking my phone's 1350mAh battery right up to 100% charge.
I combine this with the Hama Piccolino USB charger, which is another 11g (0.4 Oz):
USB cables are then another 30g or so, in long lengths, or less if you can find shorter ones. Another lightweight & inexpensive option are these USB chargers from Hong Kong on eBay at around 12g. There are a few different sellers, including this one:
This combination caters for both my phone and my digital camera.