Ah, found it! I was putting together a 3.5e list of spells and abilities you can get from summoned creatures (for a summoner sorcerer I had in mind).
@4th level Mephits are indeed useful:
Air Mephit
1x Gust of wind @6th, DC14
Earth Mephit
1x soften earth and stone
Dust Mephit
1x windwall @6th, DC15
Fire Mephit
1x scorching ray @3rd
1x heat metal @6th DC14
Ice Mephit
1x magic missile @3rd
1x chill metal @6th DC14
Magma Mephit
1x pyrotechnics @3rd DC14
Ooze
1x acid arrow @3rd
1x stinking clout @6th, DC15
Salt
1x Glitterdust @3rd, DC14
1x 20ft radius dessicate, 2d8 DC14
Steam
1x 20ft radius boiling rainstorm, 2d6 DC14
Water
1x acid arrow @3rd
1x stinking cloud @6th DC15
Alongside the aforementioned lantern archon
Archon, lantern
Aid, detect evil, continual flame at will;
Aura of menace, magic circle against evil, tongues
@5th level
Archon, hound
Aid, continual flame, detect evil, message;
Aura of menace, magic circle against evil, tongues
Achaierai
Black Cloud (2d6 + insanity) DC15
(the 3.0e bearded devil had plenty of neat spell-like abilities, sadly he was stripped of them in 3.5e...
@6th
Bralani (eladrin)
At will— blur, charm person (DC 13), gust of wind (DC 14), mirror image, wind wall;
2/day—lightning bolt (DC 15), cure serious wounds (DC 15). Caster level 6th
tongues;
whirlwind blast
Janni (genie)
3/day—invisibility (self only), speak with animals. Caster level 12th. Once per day a janni can create food and water (caster level 7th) and can use ethereal jaunt (caster level 12th) for 1 hour(?maybe not if summoned?)
@7th
Avoral (guardinal)
At will—aid, blur (self only), command (DC 14), detect magic, dimension door, dispel magic, gust of wind (DC 15), hold person (DC 16), light, magic circle against evil (self only), magic missile, see invisibility;
3/day—lightning bolt (DC 16). Caster level 8th.
Lay on hands (66hp)
Speak with animals
True seeing
Djinni (genie)
At will—invisibility (self only); 1/day— create food and water, create wine (as create water, but wine instead), major creation (created vegetable matter is permanent), persistent image (DC 17), wind walk. Once per day, a djinni can assume gaseous form (as the spell) for up to 1 hour. Caster level 20th
Devil, bone
At will—dimensional anchor, fly, invisibility (self only), major image (DC 15), wall of ice. Caster level 12th
Babau (demon)
At will—darkness, dispel magic, see invisibility
@8th
Lillend
Typical Bard Spells Known (3/4/3; save DC 14 + spell level): 0— dancing lights, daze, detect magic, lullaby, mage hand, read magic; 1st— charm person, cure light wounds, identify, sleep; 2nd—hold person, invisibility, sound burst.
3/day—darkness, hallucinatory terrain (DC 18), knock, light; 1/day—charm person (DC 15), speak with animals, speak with plants. Caster level 10th.
Vrock (demon)
At will—mirror image, telekinesis (DC 18),
1/day—heroism. Caster level 12th
Spores
Stunning Screech DC22
@9th
Couatl
Psionics (Sp): At will—detect chaos, detect evil, detect good, detect law, detect thoughts (DC 15), invisibility, plane shift (DC 20), polymorph (self only). Effective caster level 9th.
Typical Spells Known (6/7/7/7/4; save DC 13 + spell level): 0—cure minor wounds, daze, disrupt undead, light, obscuring mist, ray of frost, read magic, resistance; 1st—endure elements, mage armor, protection from chaos, true strike, wind wall; 2nd—cure moderate wounds, eagle’s splendor, scorching ray, silence; 3rd—gaseous form, magic circle against evil, summon monster III; 4th— charm monster, freedom of movement.
Leonal (guardinal)
At will—detect thoughts, fireball (DC 15), hold monster (DC 17), polymorph, wall of force;
3/day—cure critical wounds (DC 16), neutralize poison, remove disease; 1/day—heal (DC 18). Caster level 10th
Roar (holy word) 3/day
Lay on hands (114hp)
Protective Aura 20ft radius (+4 deflection, +4 resistance & lesser globe)
Devil, barbed
At will—hold person (DC 16), major image (DC 17), scorching ray (2 rays only).
1/day—order’s wrath (DC 18), unholy blight (DC 18). Caster level 12th
Night hag
At will—detect chaos, detect evil, detect good, detect law, detect magic, magic missile, polymorph (self only), ray of enfeeblement (DC 12), sleep (DC 12). Caster level 8th
Hezrou (demon)
At will—chaos hammer (DC 18), unholy blight (DC 18);
3/day—blasphemy (DC 21), gaseous form. Caster level 13th
Stench DC24
Probably not an exhaustive list, but interesting nonetheless (and much less powerful than it was in 3.0 days as I mentioned before!)
Cheers