We have a few good ones to list so let's get started.
VP8LP this station is heard often 7.147 0850Z Good catch on 40.
TL0A Very active,10.110 0100Z,28.005 1700Z.
9N7WE spotted for four contacts in North America, west coast and Midwest. 14.195 0140Z. This may be part of the group operating from 9N.
H44GC back in H44 18.145 2100Z,18.070 2020Z, 21.265 2300Z.
V6Z has been showing up for a few contacts 21.270 2100Z,21.023 2055Z
A word about Pirates and Slims as fake stations are labeled. Once in a while you have old slim showing up on the bands, he usually bootleggs the call of the most recent expedition, but not always. The other day I saw someone proclaim that TL0A was a slim and was operating on 21.005. Same base their groundless knowledge on the fact a call is not listed in QRZ, well, that is not really a good indication, but can be helpful. Let's say you visit a foreign country, get a license, walk out the door and start operating. No, you may not be QRZ right away, it may take a couple of days. So often someone was stating a station was a Slim based on the fact that they were not listed, wait a day, or two and then check. Instant exchange of information is the common practice in most countries, but some third world countries do not have internet access.
Another indication and perhaps the most reliable are beam headings, compare the beam headings of say TL0A on one day and look at him the next. If the beam heading is way off, say to the South, or some direction you know is not right, chances are you may be hearing a slim. Not always of course is this true, there is an old adage "Work it first, ask Questions Later" so true, worst that could happen is you receive a note saying "Not in Log", or you could have that rare one confirmed.