Johan Schalin’s site has a discussion of early IE loanwords in Finnish.

http://tcoimom.suntuubi.com/?cat=10

(After reading that, use the tabs “On substitutions”, “Abbreviations” and “To the Lexicon").

Finnish has sometimes been compared to a “freezer” because once a word was borrowed it has often changed much less than its original.
For example the word kuningas ‘king’ gives us independent information about Proto-Germanic, validating the data produced by theoretical reconstruction methods. In much the same way the Finnish word kulke- ‘to go, wander, move’ gives us valuable independent information about Proto-Indo-European (PIE) , for which a verb root *kw(e)lH-e- (*kw(e)lH-o-) ‘go, wander, move’ has been reconstructed.

I’ve never previously thought about early PIE loanwords in non-PIE languages being used in reconstructive efforts. I found it an interesting read.

Interesting yes, but what are the author’s credentials?

Well, he’s published an article in Virittäjä, the main Finnish linguistic journal, which at least shows he’s not a crackpot.  And his home page has a great list of linguistic resources; thanks for the heads-up!

(It’s not controversial at all that there are ancient IE loanwords in Finnish; the kuningaz thing is taught in introductory textbooks.)

Publication in a main journal is hardly evidence of non-crackpot status…

Well look, there doesn’t seem to be anything fringey or outlandish about this material. The existence of loanwords from PIE in Uralic languages isn’t news. For me, the novelty (because of my relative ignorance, I suppose) was the use of these loanwords in reconstructing PIE. I had only heard of words in IE languages being used for that purpose.