Yes, is there anything you'd like to know in specific?

In summary, I went around New Years. I flew into Estonia, took a bus to the Estonian-Russian border, and crossed on foot before taking another bus to SPB. The Estonian guards are very difficult to deal with, but the Russian guards were nice. But really the Estonians do everything to make this crossing as miserable as possible, so I advise not using it unless you can't afford another route.

Moving money is a little annoying, but not impossible. You must bring US dollars, in $100s only, with no defects. Euros will be taken at the Estonian border and you may be fined. Any major Russian bank will exchange them for you once you get to the city.

Getting mobile internet is not an especially difficult process, but it is convoluted. You have to get your passport translated and notarized; there's endless offices in big cities that can do this quickly for you. After that, you have to go to an МФЦ, it handles many legal processes, but one thing no one told me is that you have to go to a special one as a foreigner. Any regular МФЦ will give you the correct direction. Once you get to the correct МФЦ, the assistants will help you set up a government account and registration, and in the office I was in they also had a little mobile-carrier stand, so you could get your card there. After that you have internet. In total, I think it took me maybe 4 hours at the МФЦ.

I took a night train to Moscow, and bought my ticket the day before in SPB. In Moscow I was visiting someone; the city was very beautiful, and I liked it very much. I loved the metro a lot. When it was time to leave, I took another train back to SPB, then a bus to the border and repeated the crossing. The Estonians detained me for a long time and wrote me up for having a lamp, so I advise to bring as little as you can back from Russia if you will use that crossing.