Some modal Tahari T's from TJMaxx, in a few different colors, that similar to Gaylene's post, just seem to have the right neckline, sleeve length, ease of fit--neither too tailored or too fluid. I can't make myself give them away because at times they are just the perfect thing. I tend to keep them more for layering under blazers but it's okay if I need to remove the jacket.
A navy thick cotton knit top, ottoman knit, boatneck, slightly boxy, from Gap that looks better than a T but goes well over pencil skirts for a neutral summer look. I keep thinking it ought to have faded from love by now but I've not found anything that works as reliably.
Some belts from TJMaxx.
Some black suede slightly pointy toe low-heeled pumps that may finally die in the next year if the lining deteriorates--can't remember brand, a common one, not Naturalizer but similar, bought at discount store maybe 15 years ago or more--still look classic and "elevate" skirts and pants to look a bit more dressy, but are comfortable enough for some days at work.
Reliable--I think that's a key term for me. Something that even if I'm doing a review and making myself think about whether it's dated or not useful, but then I put it on and it works every time.