I work as a support technician, which means I'm frequently working on customer systems remotely. The unfortunate side effect is that I rarely have any choice over what editor I get to use in those situations. Generally speaking there's not a whole lot you can do about it unless the situation is one where it's feasible for you to install a new editor or bring a USB thumb drive or something similar with your editor pre-installed on it. In such a situation, by all means, if you plan to be working for an extended time period, take advantage of the opportunity. You'll work faster and more efficiently and it will be less frustrating.
In an environment (e.g. webex/RDC) where you cannot install software or use temporary media, you have two choices: live with whatever editor they have, or copy files back and forth from your system. Typically if I'm doing very minor editing I just suck it up and use whatever editor is available. If I know I'm going to be doing an extensive amount of editing, I find a way to transfer the file I'm working on back and forth. This still stinks, forcing you to interrupt your editing flow with file transfers, but I find my sanity makes it worth not struggling with something like notepad to do real editing or programming.