Nokia 3310
Indestructible, and the benchmark for every phone since.
Snake II, composer ringtones, and a reputation for surviving anything, which was mostly deserved.
The composer let you type in ringtones note by note, and there were magazines that printed the note sequences for chart songs.
It is the most memed phone in history and Nokia relaunched it in 2017 on the strength of the nostalgia alone.
Cost back then
£129
Goes for now
£30–£90 for originals