AT @ 25NL

Full Tilt Poker
No Limit Holdem Ring game
Blinds: $0.10/$0.25
5 players
Converter

Stack sizes:
Hero: $37.95
CO: $26
Button: $25.60
SB: $52.95
BB: $25

Pre-flop: (5 players) Hero is UTG with Ts Ac
Hero raises to $0.85, 3 folds, BB calls $0.6 (pot was $1.2).

Flop: 7s Th :8h ($1.8, 2 players)
BB checks, Hero bets $1.8, BB raises to $3.6, Hero ... ?

Only read: BB kept his stack topped up to maximum.

Call and see what he does on the turn. If he is a constant toper-upper he will know what a c-bet is and will try and blow you off your AK etc. on boards this.

He will probably have something to bet with, small pockets etc are likley as is two big hearts.