Alterations -  Here is a look at Spider-Man's costumes that are just altered in one way or another...The alteration can be either cosmetically or it can serve a purpose with the prominent alteration being that of the fan favorite black costume in either the alien or non-alien form...See for yourself:

Alien Symbiote Black Costume

 The costume that was heralded as Spider-Man's new costume back in Amazing Spider-Man #252...The costume made it's debut in Secret Wars #8 as Spider-Man on the Beyonder's planet during the Secret Wars...Spider-Man tried to replace his costume with a new one from an alien device that created new costumes...Well, he used the wrong one and an alien black substance formed over his body becoming a "costume"...The Alien Black costume was able to produce it's own unlimited webbing and it wasn't until Amazing Spider-Man #258 that it was realized that the costume was alien in nature with help from Reed Richards. The costume broke free from containment and went on to take on it's first host, an unnamed man from Indiana in Spectacular Spider-Man #99. It eventually met it's "master" in Eddie Brock and later went on to become part of Venom when bonded with Brock.

Regular Black Costume

Spectacular Spider-Man #99 was the issue that featured the 1st non-alien black costume sewn by the Black Cat for Spider-Man to wear...He resisted at first stating he got the "Heebie Jeebies" thinking about the alien one, but had to wear it out of necessity in Amazing Spider-Man #263 when his regular costume was still not dry from being cleaned in a sink...He went on to wear both the black and regular costumes until the alien one came back to his closet cataloguing as the sewn costume...That relationship ended in Web Of Spider-Man #1 before the alien costume went on to bond with Eddie Brock becoming Venom...Peter also ceased wearing the sewn black costume due to his wife Mary Jane's fear of it and Venom.

Spider Armor

Spider-Man wore this costume in only one issue, Web Of Spider-Man #100, and one issue only....Peter created the armor to aid him in defeating the New Enforcers in that issue...It helped protect himself from Plant Man's mutant spores as well as from extreme temperature blasts wielded by Dragon Man, Eel, and Thermite...It hasn't been seen since that issue.

Ninja Spidey

Spider-Man added some rags to his costume to patch up some very torn parts of his costume in Spectacular Spider-Man #213 & #214. It gave him the appearance, at least somewhat of a ninja while battling Typhoid Mary/ Bloody Mary in those issues.

Insulated Spidey

Another one issue appearance, Amazing Spider-Man #425, showcased Spider-Man in his thermal, Insulated costume that helped take some of the impact from a much more powerful Electro and his electric blasts...This costume is quite reminiscent of the one he wore in Spectacular Spider-Man #66 where he used an old rubber air-mattress to create his first insulated costume against, of course, Electro!

Cyborg Spidey

A two issue appearance, Spider-Man #21 & #22, where a man named Oscar McDonnell gave Spider-Man a cyborg cast while his arm had a hairline fracture...It gave him full function while allowing it to heal at an accelerated rate in the middle of the Revenge Of The Sinister Six storyline.

Octo-Spidey

Near the end of Funeral For An Octopus #2, Spider-Man began to wear the harness that Otto Octavius wore as Doctor Octopus...He could hardly control the arms becoming wildly off-balance until he broke free of the harness in Funeral For An Octopus #3...He has yet to wear them again.

Unlimited

From the pages of Webspinners #13 & 14, Spider-Man was introduced to a new costume that resembled the one in the animated series...The story featured Spider-Man and Negative Zone Dusk  battling Carnage and Blastaar in the Negative Zone...It also saw the return of the Carnage Symbiote to Cletus Kasady after their return to Earth.