The next set of applications happen to run on Linux, however they're considered proprietary and offer Linux support as a secondary option. I have used both extensively and each offers different benefits that will meet with the needs of most people. Both are setup for providing remote PC support to anyone on any of the three popular desktop platforms.
TeamViewer (Wine/proprietary): If you're trying to provide remote support for friends/family/co-workers who happen to be using proprietary desktop operating systems, TeamViewer is the way to go. The software is dead-simple to install on any platform, plus it works really well behind firewalls. Features for TeamViewer include the following.
Chrome Remote Beta: (Chrome Browser/proprietary): The Chrome Remote Beta extension offers a simple means of controlling another PC remotely. The biggest downside to it, however, is the fact that it locks you into a browser setting. On top of that, it may not be the best option for enterprise environments. But through my own tests, I'd suggest that it's a natural fit for many smaller businesses looking to offer quick desktop support. Below, are the features you'll find with this Chrome extension.
So after examining all of these options, which remote desktop solution is the best? Based on my own usage, I think it comes down to what you're looking for. For help desktop solutions, the Chrome Remote Beta extension is by far the easiest to use. It's fast and brain-dead simple to run.
Looking at remote access for a single user, however, I would suggest looking into Remmina. It's fairly robust and will provide you with a number of great options. Unfortunately, none of these are going to be the ultimate solution for every instance. Some enterprise users may actually find themselves in a better position using something like NoMachine's NX client/server. A bit complex for some users, NX does offer some interesting perks for enterprise situations. It's considered enterprise-friendly and might be the best fit of all.