To provide the solution for those who have given up, without spoiling it for those still trying, a fun technique is to set the font colour of the answer to white. This makes it invisible until it is highlighted by moving the cursor across while holding the left click down (as if selecting for copy).
The answer to this one is inside the speech marks "UNDER ATTACK"
I can see that Monica and myself 'liked' the posts, but we didn't want to spoil things by giving away the answers too soon. Then we forgot all about it for a few months! I will give it a couple of days before revealing them. Can you beat me to it?
LOOK SHARP! AGNETHA IN ONLY SUMMER GIG -> LOOK AGNETHA SHARP GIG ONLY IN SUMMER ->LIKE OOAGNTHA SHARP GIG ONLYN SUMMER -> LIKE AN OOGTHA SHARP GIG ONLYN SUMMER -> LIKE AN ANGEL OOGTHSHARPIG ONYSUMMR -> LIKE AN ANGEL PASS OOGTHHRIG ONYUMMR ->LIKE AN ANGEL PASSING OOGTHHROYUMMR ->LIKE AN ANGEL PASSING THROUGH OOYMMR ->LIKE AN ANGEL PASSING THROUGH YM OOMR -> LIKE AN ANGEL PASSING THROUGH MY ROOM LIKE AN ANGEL PASSING THROUGH MY ROOM
The long characters of ABBA's song is too obvious.
ABBA: aka Anni-Frid Lyngstad and her Intergalactic Trios
"Anni-Frid Lyngstad is ABBA. She is the band. We're her messengers. She is all of it. Period. We're nothing. She's everything."
^^ The idea behind ABBAgrams though, is not so much that they are difficult to solve, but that they are difficult to devise. The anagram itself should have some vaguely plausible ABBA connotation, rather than just being a nonsense sentence.
Hang on, I'll come up with a new one as an example..
(I like the non-English angle though, it opens up more opportunities)