In reply to mmmhumous:
> The standard bowline ... looks simple enough to tie and check if it's tied correctly, but how does it compare to the figure eight in terms of strength?
It should be the unanimous opinion that a single bowline devoid of anything to secure it --further tucking, or a "back-up"/"safety" knot-- is unsafe for tying in. It is not a question of strength but of its vulnerability to loosen, in firm, slick cordage such as kernmantle ropes of rockclimbing, caving, SAR, & canyon(eer)ing. Again, a single bowline needs some security measure taken.
(Regarding strength, a similar issue was raised in a sailing forum re the bowline (unsecured) vs. eye splice, and a couple respondents remarked that after some hurricane had come through and wrecked both boats and docks, that no dock line had failed at the bowline (a few, from chafe or cutting elsewhere).)
Here is an Australian PDF on bowlines, showing some uncommon ones among the more familiar.
www.paci.com.au/downloads_public/knots/02_Bowlines.pdf
The author seems to like the "Yosemite" finish, and attaches it to about everything. I think the better choices are #22-3, 30-1, 32-3. Note that the latter two knots' extra tail tuck can be applied to a two-turn ("double") bowline, for added snugness, and if anything some more material to absorb shock.
NB: If need be, both #6/7 (Yosemite) & #8/9 (similar, but more easily formed, esp. w/firm rope) can be tied **in the bight** (i.e., middle of rope, no ends).
The last-shown bowline variant ("Mirrored Bowline") is pictured too tightly drawn up; it should be more loosely dressed esp. on the mainline end, but it won't loosen further. It's just a larkshead base knot with the tail doing a bowline collaring on both ends of it. Same tucking can be applied to the clove hitch (making a water bowline extension).
*kN*