I’ve been a regular user of OnSpeed (www.onspeed.com) for a few years now, and even though the dial-up modem lines it was designed for are long-gone, I still use it on a regular basis when travelling.
Firstly – it works. I typically get 3-5x compression when using it, which means my web browsing is 3-5x faster, and the data charges are 3-5x less. In fact, the £24.99 annual charge pays for itself in the first week – half in roaming data charges, half in time saved when on a GPRS link.
I also often find myself on slow WiFi hotspots – such as the mobile ones on train broadband (National Express East Coast, Heathrow Express). Again – OnSpeed means my connection is usable.
Finally – since the link is compressed, it’s not plain-text readable; a bonus, if there’s a casual eavesdropper on the WiFi, such as on a rogue hotspot.
Oh, and second-finally – the proxy is in the UK, so if you use a service that requires a UK presence (eg. local websites), then this may help. It doesn’t work with BBC iPlayer unfortunately, as the streaming connection is ignored by OnSpeed.
But still – it’s pretty much an all-win, no-lose situation. I’d recommend OnSpeed – or a similar proxied-compression service – to any regular traveller.