• Pentel EnerGel Euro Gel Ink Pen - 0.7 mm; writes smoothly and comes in really small point sizes too
• Marvy 4300 LePen Porous Point Marker Pen - Fine Point; small profile, writes like a dream, great for a variety of paper types
• Pilot G-2 Gel Ink Pen - 0.5 mm; you can find these in a lot of places, including drugstores; also takes Mont Blanc refills in case you want to upgrade the ink quality. (link)
• Pentel Sign Pen - Fine Point; super cheap, available at most art stores, comes in a rainbow of colors, great for writing, doodling, hand lettering, etc.

All links are to JetPens, which is an awesome store for buying pens, stationery, etc.

Space pen. There are a ton of different ones out there. Try them out. They never smudged on me or stop ink flow until the ink actually runs out.

I use these everyday at school and really like them! They are very comfortable to hold, even for a long period of time, and I find it easier to have a good looking handwriting with these than with any other pen I tried (although my handwriting is still far from beautiful, but I guess that's my fault).

Pilot G Tec C4

Flows beautifully .

Uni-ball 207 and Pilot G-2 were my favorite pens in college for note taking, except for the fact that I'm a lefty and the ink always smudged because my hand would go over it before it dried.

I absolutely love Sharpie Fine Point Pens (0.5mm). These are felt tip so they dry quickly and don't smudge (another plus is you can vary line pressure so it's great for sketching)

It's all preference. Different inks, and tips will behave differently and make the pen feel different on paper. I like smooth feeling pens, so I go for large ball points with viscous ink. My favorite so far is the Fisher Space pen. They always work, are all metal, they have a really comfy shape (no hard edges), and are quite portable. It's gonna cost you more than a pack of uni-balls, but if it's something you care about that shouldn't stop you.