The TomTom RDS-TMC Traffic Receiver gets real-time traffic information for TomTom satnavs. For the one-off cost of the receiver, you can get traffic updates and let your TomTom reroute you around congestion.
By simply connecting the TomTom device to the RDS-TMC Traffic Receiver, you will automatically receive traffic information via the TMC connection. Once a journey is planned, traffic alerts which relate to the route are displayed in the traffic bar on the right hand side of the screen. When you tap the icon shown in the traffic bar, you will receive further information, such as the cause or kind of delay to traffic, such as an accident or traffic jam.
The receiver is compatible with TomTom lines including Go 520, 720 and 920, GO 530, 730 and 930, as well as their Traffic variants, and One XL models (One XL and XL V2). It requires at least version 6.525 of the TomTom application.
Note: this is not the USB version of the RDS-TMC receiver, but the latest (2008) version of the receiver with the round connector (as sold for £48.93 on the TomTom Web site and at least £25 on most other sites). It cannot be used at the same time as the TomTom iPod Connect Cable, which uses the same connector.
Opinions vary widely on how well this receiver works and the quality of the data it receives, but at this price (which includes next-day delivery) it may be worth a punt. You may also get up to 3% cashback if you go via the TopCashBack site.