I was going to link to IBM Lotus Symphony[1] in response to your question but it turns out it's only tangentially related to Notes, sharing some marketing names and, eventually, included with Notes (version 8 I think).
Symphony was initially proprietary, then freeware and finally, in 2012, turned over to the ASF as a donation. It basically consisted of a typical spreadsheet, word processor, presentation suite all using ODF as a document format.
So, not what I thought I would find but still slightly related to your question...
Hah, yeah, that's a good way to put it. For some reason I had it in my head that Notes got carried along with Symphony but it turns out it was the other way around with Symphony being given away as a free add on to Notes.
I had the "pleasure" of using a Notes/Domino solution back in the mid 90's but it was only for a couple of months; when I joined they were most of the way through a migration to MS Exchange/Office. Can't say I loved/hated it with the same zeal as other posters, just didn't have enough time to form an opinion at the time.
Symphony was initially proprietary, then freeware and finally, in 2012, turned over to the ASF as a donation. It basically consisted of a typical spreadsheet, word processor, presentation suite all using ODF as a document format.
So, not what I thought I would find but still slightly related to your question...
[1] https://en.wikipedia.org/wiki/IBM_Lotus_Symphony