We are using the Eyelink 1000 system to investigate the detailed millisecond-by-millisecond processes involved in reading linguistic stimuli in both native and non-native comprehenders.
Here you find a very nice introduction to the method from the psycholinguistics group at the Humboldt-Universität zu Berlin, who recently has compiled an introductory laboratory video and a step-by-step lab procedure for visually situated language comprehension studies (reading and spoken comprehension).