For those folks with an ifizzle check this out...probly the best one ive seen to date. Imo with future potential to upload local tracks and times for analysis online, etc...

While the display is too small for use while driving unless your copilot/instructor holds it, there is a bunch of information provided, including a ghost car display that will tell you if you are ahead or behind your last lap.

Definitely not going to replace a big$$ data acquisition device, but if you want a inexpensive way to record lap info, looks like it could be fun to play with..

More info available at the developer's site.

http://gps-laptimer.de/

MANUAL LAP TIMER
✦Beautiful analog timer display with both a minute and a second hand
✦Brand your LapTimer by adding your car’s or motorcycle’s manufacturer’s logo to the timer plate
✦Realistic simulation of analog clockwork, utilizing animation and realistic sound / tick per second
✦Precise digital display of lapped time with a precision of 1/100 second
✦Two skins, one with a white clock face and one with a black clock face
✦Record and view your lapped times by track
✦View how you optimize your time. Best times and all time best times are colored blue / red
✦Countdown ticks and animation to best lap so far with adjustable countdown volume
✦Stop / Go mode and intermediate times
✦Manage your vehicles list and associate a vehicle to each timed lap
✦Localized Time and measurement system (Metric and English)
✦Comparison of intermediate and full lap times utilizing a bar chart
✦Calculation of virtually best lap time (based on intermediates / sector time

GPS DATA RECORDING INCL. LATERAL ACCELERATION
✦Full NMEA compatibility, DGPS support (WAAS / EGNOS)
✦Position, speed, height, course etc. are recorded while you’re lapping
✦Watch the recorded track, zoom in and out
✦Zoom in and watch the calculated lateral and lineal acceleration (G)
✦Extensive export functionality: JPEG, CSV, TRK, KML (GoogleEarth)
✦Real time lap to lap comparison utilizing a “shadow mode”
✦View including last straight’s top speed and last curve’s lowest speed
✦Views provided: Classic, Racer’s, Biker’s, GPS, Compass, and Lap List

POINT OF INTEREST SUPPORT
✦Import POIs from various sources and maintain them utilizing an Excel Sheet
✦POIs may trigger actions like starting or stopping a lap or taking an intermediate time
✦Manual Triggers may also be defined within LapTimer, i. e. without Excel
✦POIs are displayed in recorded maps (e. g. to document bends)
✦Alerts may be displayed when approaching a POI

ADDITIONAL FEATURES IN PRODUCT LINE PROFESSIONAL
✦Additional GPS recording information available
✦GPS preferences with receiver diagnostics
✦Support for GPS devices with update rate better than 1Hz
✦Set device’s internal time and date from GPS information received
✦GPS data recording compression (Low, High, None)
✦Fully adjustable POI / trigger detection corridor
✦GPS triggered acceleration recording, e. g. from 0 to 100km/h
✦Additional views: Regularity, Acceleration, Satellites, NMEA, POIs
✦and a lot more…

screenshots...
Snapshots (iPhone)