Here's an interesting ballpoint, the Kaweco Classic Sport. It's a small pen, measuring 4.5 inches and so it's great for carrying in a pocket. A clip is available separately if that's of interest, but the pen is faceted barrel keeps it from rolling off a table.
Something I found very interesting was the way the inside section holding the refill is all one interlocking piece. I actually can't get the ink refill out, that's how tight the fit is. Which I find a great concept, as with regular ballpoints you have different pieces that can roll all over and get lost.
Available in blue or black, mine came from Lost Crates and is burgundy with gold accents. Quite a lovely little pen, though the price is a bit steep. Writes well, but I may try to hack it with a gel ink refill to see how that works out.