Queen’s * Somebody to Love* is a slightly less ambitious version of Bohemian Rhapsody.
The Royal Guardsmen–Snoopy vs. the Red Baron, The Return of hte Red Baron, Snoopy’s Christmas.
Rats! You gave my answer! 
I saw two comedians on TV singing two of **Brittney Spear’s ** songs at the same time. It was clear that both songs had the same melody. One was Baby, one more time or such and I’m not sure what the other was.
Since Im the self-appointed not-alike police anyway:
Not alike. And Be My Baby is much better.
I don’t hear it. Bohemian is opera inspired, somebody to love is gospel inspired. They have several people singing in both of them, but that’s pretty much it.
Red Hot Chili Peppers, of course! All their songs sound the same. Hate that band. 
Nitpick: Surfin’ U. S. A. is a different set of lyrics to Chuck Berry’s Sweet Little Sixteen.
Jungle Man, I Could’ve Lied, Dani California.
Doesn’t get much more varied than that.
It always amused me that two-hit-wonders EMF followed up “Unbelievable” with the contradictory yet very similar “I Believe”.
Quarterflash. Unless you are a fan, every song is “Harden My Heart.”
You said it yourself: same tempo, lyrics, and vocal sound. Nothing on Procul Harum’s debut album (a masterpiece) sounds as much like “Whiter Shade.”
I’ve always thought Golden Earring’s Radar Love and Twilight Zone were stylistically similiar.
The Jackson 5’s “I Want You Back” and “ABC” - “ABC” is based on the chorus of “I Want You Back”.
I dunno about that. I’d say “Cerdes,” “A Christmas Camel,” “Repent Walpurgis,” maybe even “Something Following Me” have about as much in common with AWSOP as “Homburg” does. Come to think of it, “Homburg” sounds more like “Salad Days (Are Here Again)” than like AWSOP.
People disagreeing on when rock songs sound alike. You could knock me over with a tsunami.
A place where you can really hear this phenomenon at work is on any record label’s box set. Particularly labels like Cameo-Parkway and Motown, where they had staff writers and a staff band. One of their groups hits with a song, so the next batch of records to come out on the label are aping the style or content of that song, trying for a carbon-copy hit.
Nowhere is it more evident than on any of the albums by the groups on Cameo-Parkway and Motown. Holland-Dozier-Holland would write a dozen variations on a theme, get The Temptations to sing them, and maybe one would hit. The Supremes sang dozens and dozens of the most bland filler songs that try to sound like their other hits. This was such a common practice…I have the album by Steam, with “Na Na Hey Hey (Kiss Him Goodbye).” All of the other songs on it have some variation of “Na Na Hey Hey” in them somewhere, and for that reason they fail for being obvious dreck riding the coattails of a decent hook.
Anybody mention Christopher Cross, his stuff put me to sleep. His first single Sailing and then later Arthur’ Theme.
“Saturday Night at the Movies” was the second single released after “Under the Boardwalk” (all this took place in 1964). The single released immediately after “Boardwalk” was an even closer match, as “I’ve Still Got Sand in My Shoes” continued the beach theme, and even repeated the line “down by the sea” from the earlier song, just to remind you which group this was.
All Travis songs sound virtually identical.
Pearl Jam’s “Jeremy” followed by “Daughter”.