TortoiseGit provides a Revision Graph. This provides a quick overview of the existing branches (local and remote/remotes). From this overview, logs for specific branches/tags can be opened and it is very easy to switch.
Especially for new Git users this overview can be very helpful.
It would be nice to add something like this to SmartGit.
The manual and its features can be found here:
Customer support service by UserEcho