If you tend to feel a little rundown late in the day, a portable gadget charger could be just what you need.
You can charge the Powermonkey eXtreme or Droidax PortaCharge from a wall socket or a USB port, then throw it in your carry bag. If a gadget starts to run low on juice, you can plug it into the charger. The eXtreme also comes with a solar panel for when you're off the beaten track.
These two chargers are designed to power a wide range of devices, not just Apple's iGadgets, which makes them especially handy for travellers who might need to recharge a phone, tablet, music player, e-book reader, hand-held games console or wi-fi hot spot. The eXtreme has a range of adaptor plugs and the PortaCharge comes with a cumbersome 10-in-one adaptor cable. The original Powermonkey eXplorer lacks a microUSB plug, which is used by many Android devices but, thankfully, it's been added to the eXtreme and the new-model eXplorer.
The PortaCharge features a 5400mAh internal battery, which is generous considering the price, but you'll get almost twice as many recharges from the eXtreme's hefty 9000mAh battery. The trade-off is that the PortaCharge is more flexible, with two built-in USB ports for charging two devices at once, such as a smartphone and a tablet.
The Powermonkey eXtreme's large battery is attractive, but it comes with a hefty price tag. Considering the price, it's hard to go past the Droidax PortaCharge, unless you need the eXtreme's solar panel.