HSCF, Hybrid, the pewter Burger King figures if you're willing to paint them.
Here's some stuff from this thread:
dragonballfigures.com/thread/688/scale-comparison-different-lines-figuresA lot of this stuff is very rare, very expensive for what it is, and uncommon to see sold now. For example, the Frieza that comes with his hover pod (marked Y in the pic)... you'd be lucky to find it for sale probably, and if you did, it's probably in the package still and very expensive. The Burger King figures are still cheap. The Hybrid and HSCF are not.
O- Family Mart gashapon, these don't have a scale much like Megahouse and Imagination don't
P- Bandai America '96 2.5 inch figures, these don't have a scale and most are 2.5 inches tall
Q- Robust, these are (as far as I know) identical rereleases of Ultra Figus figures, not all figures were rereleased, in fact I think only about 8 were, and they come on these orange 'bottle caps'
R- Popy Mini Big Head, these are all pretty much 4.5 to 5 inch scale heads on tiny bodies
S- Bandai Chara Puchi, these are all pretty much 5 inch scale heads on small bodies, but characters with large hair don't have hair large enough to technically work on 5 inch scale bodies
T- Banpresto Dragon World Collectible/World Collectible Figure series, DWC/WCF, these are pretty much 2.5 inch figures with heads ranging from 5 inch scale to maybe 9 inch scale (mine in the picture are bootlegs)
U- Bandai Ultimate Collection, 3.75 inch scale like GI Joe and Star Wars
V- Irwin Secret Saiyan Warrior, 3.75 inch scale
W- Bandai Real Works, typically 4 inch scale
X- Legend of the Saiyan, typically 3 inches tall and NOT scaled. Some blend in with HG, while others like this one blend in with Real Works.
Y- I can't remember what this line is called, but there are small figures that come with unpainted gray model kits you build (Frieza came with his pod, Pilaf comes with his robot suit, etc.)
Z- Bandai Hybrid, they are "sort of" scaled at 4 inches, though the Gohan and DBGT kid Goku can blend into a 5 inch collection
A1- Burger King pewter colored figures, they are between 4 and 5 inch scale depending on character (Krillin and Gohan can pass for 5 inch scale, the rest cannot)
A2- High Spec Coloring Figure, HSCF, this one is a bootleg, but most of these are 4 to 4.75 inch scale. A few of the characters are 5 inch scale though, such as all of the Vegetas and Frieza form 1. To be honest, their scale isn't very strict, because characters who would need to be enormous are very small (Imperfect Cell, Frieza form 2, etc.)
A3-Irwin, 5 inch scale, most of the figures are 5 inch scale, though smaller characters were made too large
A4-Jakks Pacific, 5 inch scale, most of the figures are 5 inch scale, though smaller characters were made too large
A5- Bandai Super Battle Collection, SBC, 5 inch scale until DBGT, when they get to DBGT the scale jumps to 5.5 to 6 inch scale
A6- Banpresto DX, this line of DX figures vary between 5 and 6 inch scale (Fat Buu and Piccolo can work in a 5 inch collection, this Goku and Gohan in kai outfit cannot because they are too big)
A7- DeAgostini 5 inch scale figures, very few of the figures don't scale well
A8- Editions Atlas 5 inch scale figures, they tend to be a little taller than the DeAgostini versions, but that isn't always true because their Tien is much too small
A9- Bandai Super Battle Collection, SBC for DBGT. Technically these are bootlegs I repainted. The real ones are 1% to 5% larger and very obviously 5.5 to 6 inch scale
A10- Jakks Pacific DBGT figures, they are 6 inch scale and will not blend in with Jakks 5 inch figures mostly because of their much larger heads
A11- AB Super Guerriers, 5 inch scale
A12- AB ~2003 higher articulated figures (Bulma is a bad example of that), 5 inch scale mostly... Korin is much larger than that, and theres some other variation in there too, like Raditz being too short