There are plenty of fancy chess computers on the market these days but most of them are not portable. The Hegener + Glaser Mephisto Marco Polo is a classic travel chess computer from the 1980s that you can take anywhere to play. It has 16 LEDs to show the moves. It has 50 levels for you to choose from. It has an opening library with 300 variations.
The Mephisto Marco Polo has an opening library with 300 variations. It has an rating of about 1700 ELO.